Provided by: dialog_1.3-20160209-1_amd64 bug

NAME

       dialog - widgets and utilities for the dialog program

SYNOPSIS

       cc [ flag ... ] file ... -ldialog [ library ... ]
          or
       cc $(dialog-config --cflags) file ... $(dialog-config --libs) ]

       #include <dialog.h>

       Dialog  is  a program that will let you present a variety of questions or display messages
       using dialog boxes from a shell script.  It  is  built  from  the  dialog  library,  which
       consists  of  several widgets as well as utility functions that are used by the widgets or
       the main program.

DESCRIPTION

       This manpage documents the features from <dialog.h> which are likely to  be  important  to
       developers  using  the  widgets  directly.   Some  hints are also given for developing new
       widgets.

       Here is a dialog version of Hello World:
              int main(void)
              {
                   int status;
                   init_dialog(stdin, stdout);
                   status = dialog_yesno(
                             "Hello, in dialog-format",
                             "Hello World!",
                             0, 0);
                   end_dialog();
                   return status;
              }

DEFINITIONS

       Exit codes (passed back to the main program for its use) are  defined  with  a  "DLG_EXIT_
       prefix.   The  efined  constants can be mapped using environment variables as described in
       dialog(1), e.g., DLG_EXIT_OK corresponds to $DIALOG_OK.

       Useful character constants which correspond to  user  input  are  named  with  the  "CHR_"
       prefix, e.g., CHR_BACKSPACE.

       Colors  and  video  attributes  are  categorized  and  associated  with  settings  in  the
       configuration file (see the discussion of  $DIALOGRC  in  dialog(1)).   The  DIALOG_ATR(n)
       macro  is  used  for  defining  the  references  to the combined color and attribute table
       dlg_color_table[].

       The dialog application passes its command-line parameters to the widget  functions.   Some
       of  those parameters are single values, but some of the widgets accept data as an array of
       values.  Those include checklist/radiobox, menubox  and  formbox.   When  the  --item-help
       option is given, an extra column of data is expected.  The USE_ITEM_HELP(), CHECKBOX_TAGS,
       MENUBOX_TAGS and FORMBOX_TAGS macros are used to hide this  difference  from  the  calling
       application.

       Most of the other definitions found in <dialog.h> are used for convenience in building the
       library or main program.  These include definitions based on the generated  <dlg_config.h>
       header.

DATA STRUCTURES

       All of the global data for the dialog library is stored in a few structures: DIALOG_STATE,
       DIALOG_VARS  and  DIALOG_COLORS.   The   corresponding   dialog_state,   dialog_vars   and
       dlg_color_table  global  variables should be initialized to zeros, and then populated with
       the data to use.  A few of  these  must  be  nonzero  for  the  corresponding  widgets  to
       function.   As  as  the  case  with function names, variables beginning with "dialog_" are
       designed for use by the calling application while  variables  beginning  with  "dlg_"  are
       intended for lower levels, e.g., by the dialog library.

DIALOG_STATE

       The  state  variables  are dialog's working variables.  It initializes those, uses them to
       manage the widgets.

   .all_subwindows
       This is a linked list of all  subwindows  created  by  the  library.   The  dlg_del_window
       function uses this to free storage for subwindows when deleting a window.

   .all_windows
       This  is a linked list of all windows created by the library.  The dlg_del_window function
       uses this to locate windows which may be redrawn after deleting a window.

   .aspect_ratio
       This corresponds to  the  command-line  option  "--aspect-ratio".   The  value  gives  the
       application  some control over the box dimensions when using auto sizing (specifying 0 for
       height and width).  It represents width /  height.   The  default  is  9,  which  means  9
       characters wide to every 1 line high.

   .finish_string
       When set to true, this allows calls to dlg_finish_string to discard the corresponding data
       which is created to speed up layout computations for  the  given  string  parameter.   The
       gauge widget uses this feature.

   .getc_callbacks
       This  is  setup  in  ui_getc.c  to record windows which must be polled for input, e.g., to
       handle the background tailbox widget.  One window  is  designated  as  the  foreground  or
       control window.

   .getc_redirect
       If  the  control window for DIALOG_STATE.getc_callbacks is closed, the list is transferred
       to this variable.  Closing all windows causes the application to exit.

   .no_mouse
       This corresponds to the command-line  option  "--no-mouse".   If  true,  dialog  will  not
       initialize (and enable) the mouse in init_dialog.

   .output
       This  is  set in the dialog application to the stream on which the application and library
       functions may write text results.  Normally that is the standard error, since  the  curses
       library  prefers  to  write  its  data  to  the  standard  output.   Some scripts, trading
       portability for convenience, prefer to write results to  the  standard  output,  e.g.,  by
       using the "--stdout" option.

   .output_count
       This is incremented by dlg_does_output, which is called by each widget that writes text to
       the output.  The dialog application uses  that  to  decide  if  it  should  also  write  a
       separator, i.e., DIALOG_STATE.separate_str, between calls to each widget.

   .pipe_input
       This  is  set in init_dialog to a stream which can be used by the gauge widget, which must
       be the application's standard input.  The dialog application  calls  init_dialog  normally
       with  input  set  to  the standard input, but optionally based on the "--input-fd" option.
       Since the application cannot read from a pipe (standard input) and at the same  time  read
       the  curses  input  from  the  standard input, it must allow for reopening the latter from
       either a specific file descriptor, or directly  from  the  terminal.   The  adjusted  pipe
       stream value is stored in this variable.

   .screen_initialized
       This  is  set  in  init_dialog and reset in end_dialog.  It is used to check if curses has
       been initialized, and if the endwin function must be called on exit.

   .screen_output
       This is set in init_dialog to the output stream used by the curses library.  Normally that
       is  the  standard output, unless that happens to not be a terminal (and if init_dialog can
       successfully open the terminal directly).

   .separate_str
       This corresponds  to  the  command-line  option  "--separate-widget".   The  given  string
       specifies  a  string  that  will  separate the output on dialog's output from each widget.
       This is used to simplify parsing the result of a dialog with  several  widgets.   If  this
       option is not given, the default separator string is a tab character.

   .tab_len
       This  corresponds  to  the  command-line option "--tab-len number".  Specify the number of
       spaces that a tab character occupies if the "--tab-correct" option is given.  The  default
       is 8.

   .trace_output
       This  corresponds  to  the  command-line option "--trace file".  It is the file pointer to
       which trace messages are written.

   .use_colors
       This is set in init_dialog if the curses implementation supports color.

   .use_scrollbar
       This corresponds to the command-line option "--scrollbar".  If true, draw a  scrollbar  to
       make windows holding scrolled data more readable.

   .use_shadow
       This  corresponds to the command-line option "--no-shadow".  This is set in init_dialog if
       the curses implementation supports color.  If true, suppress shadows that would  be  drawn
       to the right and bottom of each dialog box.

   .visit_items
       This  corresponds to the command-line option "--visit-items".  Modify the tab-traversal of
       the  list-oriented  widgets  (buildlist,  checklist,  radiobox,  menubox,  inputmenu,  and
       treeview)  to  include the list of items as one of the states.  This is useful as a visual
       aid, i.e., the cursor position helps some users.

       The dialog application resets the dialog_vars data before accepting options to invoke each
       widget.   Most  of  the  DIALOG_VARS  members  are set directly from dialog's command-line
       options:

DIALOG_VARS

       In contrast to DIALOG_STATE, the members of DIALOG_VARS are set by command-line options in
       dialog.

   .ascii_lines
       This  corresponds to the command-line option "--ascii-lines.  It causes line-drawing to be
       done with ASCII characters, e.g., "+" and "-".  See DIALOG_VARS.no_lines.

   .backtitle
       This corresponds to the command-line  option  "--backtitle  backtitle".   It  specifies  a
       backtitle string to be displayed on the backdrop, at the top of the screen.

   .beep_after_signal
       This  corresponds  to  the command-line option "--beep-after".  If true, beep after a user
       has completed a widget by pressing one of the buttons.

   .beep_signal
       This corresponds to the command-line option "--beep".  It is obsolete.

   .begin_set
       This is true if the command-line option "--begin y x" was used.  It specifies the position
       of the upper left corner of a dialog box on the screen.

   .begin_x
       This corresponds to the x value from the command-line option "--begin y x" (second value).

   .begin_y
       This corresponds to the y value from the command-line option "--begin y x" (first value).

   .cancel_label
       This  corresponds  to  the  command-line option "--cancel-label string".  The given string
       overrides the label used for "Cancel" buttons.

   .cant_kill
       This corresponds to the command-line option "--no-kill".  If true, this  tells  dialog  to
       put  the  tailboxbg  box  in  the  background, printing its process id to dialog's output.
       SIGHUP is disabled for the background process.

   .colors
       This corresponds to the command-line option "--colors".  If true, interpret embedded  "\Z"
       sequences  in the dialog text by the following character, which tells dialog to set colors
       or video attributes: 0 through 7 are the ANSI codes used in  curses:  black,  red,  green,
       yellow,  blue,  magenta,  cyan  and white respectively.  Bold is set by 'b', reset by 'B'.
       Reverse is set by 'r', reset by 'R'.  Underline is set by 'u', reset by 'U'.  The settings
       are  cumulative,  e.g.,  "\Zb\Z1"  makes  the  following  text bright red.  Restore normal
       settings with "\Zn".

   .column_separator
       This corresponds to the command-line option "--column-separator".  Dialog splits data  for
       radio/checkboxes  and  menus  on the occurrences of the given string, and aligns the split
       data into columns.

   .cr_wrap
       This corresponds to the command-line option  "--cr-wrap".   If  true,  interpret  embedded
       newlines  in the dialog text as a newline on the screen.  Otherwise, dialog will only wrap
       lines where needed to fit inside the text box.  Even though you can  control  line  breaks
       with  this,  dialog  will still wrap any lines that are too long for the width of the box.
       Without cr-wrap, the layout of your text may be formatted to look nice in the source  code
       of your script without affecting the way it will look in the dialog.

   .date_format
       This  corresponds to the command-line option "--date-format string".  If the host provides
       strftime, and the value is nonnull, the calendar widget uses this to format its output.

   .default_button
       This  is  set  by  the   command-line   option   "--default-button.    It   is   used   by
       dlg_default_button.

   .default_item
       This  corresponds to the command-line option "--default-item string".  The given string is
       used as the default item in a checklist, form or menu box.  Normally the first item in the
       box is the default.

   .defaultno
       This  corresponds  to  the  command-line  option "--defaultno".  If true, make the default
       value of the yes/no box a No.  Likewise, make the default button of widgets  that  provide
       "OK"  and  "Cancel"  a Cancel.  If --nocancel was given that option overrides this, making
       the default button always "Yes" (internally the same as "OK").

   .dlg_clear_screen
       This corresponds to the command-line option "--clear".  This option is implemented in  the
       main  program, not the library.  If true, the screen will be cleared on exit.  This may be
       used alone, without other options.

   .exit_label
       This corresponds to the command-line  option  "--exit-label  string".   The  given  string
       overrides the label used for "EXIT" buttons.

   .extra_button
       This  corresponds to the command-line option "--extra-button".  If true, some widgets show
       an extra button, between "OK" and "Cancel" buttons.

   .extra_label
       This corresponds to the command-line option  "--extra-label  string".   The  given  string
       overrides  the label used for "Extra" buttons.  Note: for inputmenu widgets, this defaults
       to "Rename".

   .formitem_type
       This is set by the command-line option "--passwordform" to tell the form widget  that  its
       text fields should be treated like password widgets.

   .help_button
       This corresponds to the command-line option "--help-button".  If true, some widgets show a
       help-button after "OK" and "Cancel" buttons, i.e., in checklist, radiolist and menu boxes.
       If  --item-help  is also given, on exit the return status will be the same as for the "OK"
       button, and the item-help text will be written to dialog's output after the token  "HELP".
       Otherwise,  the  return  status  will  indicate  that  the Help button was pressed, and no
       message printed.

   .help_file
       This corresponds to the command-line option  "--hfile  string".   The  given  filename  is
       passed to dialog_helpfile when the user presses F1.

   .help_label
       This  corresponds  to  the  command-line  option  "--help-label string".  The given string
       overrides the label used for "Help" buttons.

   .help_line
       This corresponds to the  command-line  option  "--hline  string".   The  given  string  is
       displayed in the bottom of dialog windows, like a subtitle.

   .help_status
       This  corresponds  to the command-line option "--help-status".  If true, and the the help-
       button is selected, writes the checklist or  radiolist  information  after  the  item-help
       "HELP"  information.   This  can  be  used  to  reconstruct the state of a checklist after
       processing the help request.

   .help_tags
       This corresponds to the command-line option "--help-tags".  If true, dlg_add_help_formitem
       and  dlg_add_help_listitem  use  the  item's  tag value consistently rather than using the
       tag's help-text value when DIALOG_VARS.item_help is set.

   .input_length
       This is nonzero if DIALOG_VARS.input_result is allocated, versus being a  pointer  to  the
       user's local variables.

   .input_menu
       This flag is set to denote whether the menubox widget implements a menu versus a inputmenu
       widget.

   .input_result
       This may be either a user-supplied buffer,  or  a  buffer  dynamically  allocated  by  the
       library, depending on DIALOG_VARS.input_length:

       •   If  DIALOG_VARS.input_length  is zero, this is a pointer to user buffer (on the stack,
           or static).  The buffer size is assumed to be MAX_LEN, which is defined in <dialog.h>.

       •   When DIALOG_VARS.input_length is nonzero, this is a dynamically-allocated buffer  used
           by the widgets to return printable results to the calling application.

       Certain widgets copy a result to this buffer.  If the pointer is NULL, or if the length is
       insufficient for the result, then the dialog library allocates a  buffer  which  is  large
       enough,  and  sets  DIALOG_VARS.input_length.   Callers should check for this case if they
       have supplied their own buffer.

   .insecure
       This corresponds to the command-line option "--insecure".   If  true,  make  the  password
       widget friendlier but less secure, by echoing asterisks for each character.

   .in_helpfile
       This  variable  is used to prevent dialog_helpfile from showing anything, e.g., if F1 were
       pressed within a help-file display.

   .iso_week
       This corresponds to the command-line option "--iso-week".  It  is  used  in  the  calendar
       widget to tell how to compute the starting week for the year:

       •   by default, the calendar treats January 1 as the first week of the year.

       •   If  this  variable is true, the calendar uses ISO 8601's convention.  ISO 8601 numbers
           weeks starting with the first week in January with a Thursday  in  the  current  year.
           January 1 may be in the previous year.

   .item_help
       This  corresponds  to  the command-line option "--item-help".  If true, interpret the tags
       data for checklist, radiolist and menu boxes adding a column whose text  is  displayed  in
       the bottom line of the screen, for the currently selected item.

   .keep_tite
       This  is  set  by  the  command-line option "--keep-tite" to tell dialog to not attempt to
       cancel the terminal initialization (termcap ti/te) sequences which correspond  to  xterm's
       alternate-screen  switching.   Normally  dialog  does  this  to  avoid flickering when run
       several times in a script.

   .keep_window
       This  corresponds  to  the  command-line  option  "--keep-window".   If   true,   do   not
       remove/repaint the window on exit.  This is useful for keeping the window contents visible
       when several widgets are run in the same process.  Note that curses will clear the  screen
       when starting a new process.

   .last_key
       This corresponds to the command-line option "--last-key".

   .max_input
       This  corresponds  to  the command-line option "--max-input size".  Limit input strings to
       the given size.  If not specified, the limit is 2048.

   .no_items
       This corresponds to  the  command-line  option  "--no-items".   Some  widgets  (checklist,
       inputmenu,  radiolist,  menu)  display  a list with two columns (a "tag" and "item", i.e.,
       "description").  This tells dialog to read shorter rows from data, omitting the "list".

   .no_label
       This corresponds to  the  command-line  option  "--no-label  string".   The  given  string
       overrides the label used for "No" buttons.

   .no_lines
       This corresponds to the command-line option "--no-lines.  It suppresses line-drawing.  See
       DIALOG_VARS.ascii_lines.

   .no_nl_expand
       This corresponds to the command-line option "--no-nl-expand".  If  false,  dlg_trim_string
       converts literal "\n" substrings in a message into newlines.

   .no_tags
       This  corresponds  to  the  command-line  option  "--no-tags".   Some  widgets (checklist,
       inputmenu, radiolist, menu) display a list with two columns  (a  "tag"  and  "item",  also
       known as "description").  The tag is useful for scripting, but may not help the user.  The
       --no-tags option (from Xdialog) may be used to  suppress  the  column  of  tags  from  the
       display.

       Normally dialog allows you to quickly move to entries on the displayed list, by matching a
       single character to the first character of the tag.  When the --no-tags option  is  given,
       dialog  matches  against  the  first  character  of  the description.  In either case, the
       matchable character is highlighted.

       Here is a table showing how the no_tags and no_items values interact:

       Widget      Fields Shown   Fields Read   .no_items   .no_tags
       ──────────────────────────────────────────────────────────────
       buildlist   item           tag,item          0          0*
       buildlist   item           tag,item          0          1
       buildlist   tag            tag               1          0*
       buildlist   tag            tag               1          1

       checklist   tag,item       tag,item          0          0
       checklist   item           tag,item          0          1
       checklist   tag            tag               1          0
       checklist   tag            tag               1          1
       inputmenu   tag,item       tag,item          0          0
       inputmenu   item           tag,item          0          1
       inputmenu   tag            tag               1          0
       inputmenu   tag            tag               1          1
       menu        tag,item       tag,item          0          0
       menu        item           tag,item          0          1
       menu        tag            tag               1          0
       menu        tag            tag               1          1
       radiolist   tag,item       tag,item          0          0
       radiolist   item           tag,item          0          1
       radiolist   tag            tag               1          0
       radiolist   tag            tag               1          1
       treeview    item           tag,item          0          0*
       treeview    item           tag,item          0          1
       treeview    tag            tag               1          0*
       treeview    tag            tag               1          1
       ──────────────────────────────────────────────────────────────

       * Xdialog does not display the  tag  column  for  the  analogous  buildlist  and  treeview
         widgets.   Dialog  does  the  same  on  the command-line.  However the library interface
         defaults to displaying the tag column.  Your application can enable or disable  the  tag
         column as needed for each widget.

   .nocancel
       This corresponds to the command-line option "--no-cancel".  If true, suppress the "Cancel"
       button in checklist, inputbox and menu box modes.  A script can still  test  if  the  user
       pressed the ESC key to cancel to quit.

   .nocollapse
       This  corresponds  to  the  command-line option "--no-collapse".  Normally dialog converts
       tabs to spaces and reduces multiple spaces to a single space for text which  is  displayed
       in  a message boxes, etc.  It true, that feature is disabled.  Note that dialog will still
       wrap text, subject to the --cr-wrap option.

   .nook
       This corresponds to the command-line option "--nook.  Dialog will suppress  the  "ok"  (or
       "yes") button from the widget.

   .ok_label
       This  corresponds  to  the  command-line  option  "--ok-label  string".   The given string
       overrides the label used for "OK" buttons.

   .print_siz
       This corresponds to the command-line option "--print-size".  If true, each  widget  prints
       its size to dialog's output when it is invoked.

   .quoted
       This corresponds to the command-line option "--quoted.

   .separate_output
       This  corresponds  to  the  command-line  option  "--separate-output".  If true, checklist
       widgets output result one line at a time, with no quoting.  This  facilitates  parsing  by
       another program.

   .single_quoted
       This  corresponds  to  the  command-line  option  "--single-quoted".  If true, use single-
       quoting as needed (and no quotes if unneeded) for the output of checklist's as well as the
       item-help  text.   If  this option is not set, dialog uses double quotes around each item.
       The latter requires occasional use of backslashes to  make  the  output  useful  in  shell
       scripts.

   .size_err
       This  corresponds  to  the command-line option "--size-err".  If true, check the resulting
       size of a dialog box before trying to use it, printing the resulting size if it is  larger
       than the screen.  (This option is obsolete, since all new-window calls are checked).

   .sleep_secs
       This corresponds to the command-line option "--sleep secs".  This option is implemented in
       the main program, not the library.  If nonzero, this is the number  of  seconds  after  to
       delay after processing a dialog box.

   .tab_correct
       This  corresponds  to  the command-line option "--tab-correct".  If true, convert each tab
       character of the text to one or more spaces.  Otherwise, tabs are  rendered  according  to
       the curses library's interpretation.

   .time_format
       This  corresponds to the command-line option "--time-format string".  If the host provides
       strftime, and the value is nonnull, the timebox widget uses this to format its output.

   .timeout_secs
       This corresponds to the command-line option "--timeout secs".  If nonzero,  timeout  input
       requests (exit with error code) if no user response within the given number of seconds.

   .title
       This  corresponds to the command-line option "--title title".  Specifies a title string to
       be displayed at the top of the dialog box.

   .trim_whitespace
       This corresponds to the command-line option "--trim".  If true, eliminate leading  blanks,
       trim literal newlines and repeated blanks from message text.

   .week_start
       This  corresponds  to  the command-line option "--week-start".  It is used in the calendar
       widget to set the starting day for the week.  The string value can be

       •   a number (0 to 6, Sunday through Saturday using POSIX) or

       •   the special value  "locale"  (this  works  with  systems  using  glibc,  providing  an
           extension to the locale command, the first_weekday value).

       •   a  string  matching  one  of  the  abbreviations  for the day of the week shown in the
           calendar widget, e.g., "Mo" for "Monday".

   .yes_label
       This corresponds to the  command-line  option  "--yes-label  string".   The  given  string
       overrides the label used for "Yes" buttons.

WIDGETS

       Functions  that  implement  major functionality for the command-line dialog program, e.g.,
       widgets, have names beginning "dialog_".

       All dialog boxes have at least three parameters:

          title
               the caption for the box, shown on its top border.

          height
               the height of the dialog box.

          width
               the width of the dialog box.

       Other parameters depend on the box type.

   dialog_buildlist
       implements the "--buildlist" option.

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is the desired height of the box.  If  zero,  the  height  is  adjusted  to  use  the
            available screen size.

       int width
            is  the  desired  width  of  the  box.   If  zero,  the height is adjusted to use the
            available screen size.

       int list_height
            is the minimum height to reserve for displaying the list.  If zero,  it  is  computed
            based on the given height and width.

       int item_no
            is the number of rows in items.

       char ** items
            is an array of strings which is viewed either as a list of rows
            tag item status

            or
            tag item status help

            depending on whether dialog_vars.item_help is set.

       int order_mode
            is reserved for future enhancements

   dialog_calendar
       implements the "--calendar" option.

       const char * title
            is the title on the top of the widget.

       const char * subtitle
            is the prompt text shown within the widget.

       int height
            is the height excluding the fixed-height calendar grid.

       int width
            is  the overall width of the box, which is adjusted up to the calendar grid's minimum
            width if needed.

       int day
            is the initial day of the week shown, counting zero  as  Sunday.   If  the  value  is
            negative, the current day of the week is used.

       int month
            is  the  initial  month  of the year shown, counting one as January.  If the value is
            negative, the current month of the year is used.

       int year
            is the initial year shown.  If the value is negative, the current year is used.

   dialog_checklist
       implements the "--checklist" and "--radiolist" options depending on the flag parameter.

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is the desired height of the box.  If  zero,  the  height  is  adjusted  to  use  the
            available screen size.

       int width
            is  the  desired  width  of  the  box.   If  zero,  the height is adjusted to use the
            available screen size.

       int list_height
            is the minimum height to reserve for displaying the list.  If zero,  it  is  computed
            based on the given height and width.

       int item_no
            is the number of rows in items.

       int items
            is an array of strings which is viewed either as a list of rows
            tag item status

            or
            tag item status help

            depending on whether dialog_vars.item_help is set.

       flag is either FLAG_CHECK, for checklists, or FLAG_RADIO for radiolists.

   dialog_dselect
       implements the "--dselect" option.

       const char * title
            is the title on the top of the widget.

       const char * path
            is  the  preselected  value  to  show in the input-box, which is used also to set the
            directory- and file-windows.

       int height
            is the height excluding the minimum needed to show  the  dialog  box  framework.   If
            zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

   dialog_editbox
       implements the "--editbox" option.

       const char * title
            is the title on the top of the widget.

       const char * file
            is the name of the file from which to read.

       int height
            is  the  desired  height  of  the  box.   If  zero, the height is adjusted to use the
            available screen size.

       int width
            is the desired width of the box.   If  zero,  the  height  is  adjusted  to  use  the
            available screen size.

   dialog_form
       implements the "--form" option.

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is  the  desired  height  of  the  box.   If  zero, the height is adjusted to use the
            available screen size.

       int width
            is the desired width of the box.   If  zero,  the  height  is  adjusted  to  use  the
            available screen size.

       int form_height
            is  the  minimum  height to reserve for displaying the list.  If zero, it is computed
            based on the given height and width.

       int item_no
            is the number of rows in items.

       int items
            is an array of strings which is viewed either as a list of rows
            Name NameY NameX Text TextY TextX FLen ILen

            or
            Name NameY NameX Text TextY TextX FLen ILen Help

            depending on whether dialog_vars.item_help is set.

   dialog_fselect
       implements the "--fselect" option.

       const char * title
            is the title on the top of the widget.

       const char * path
            is the preselected value to show in the input-box, which is  used  also  to  set  the
            directory- and file-windows.

       int height
            is  the  height  excluding  the  minimum needed to show the dialog box framework.  If
            zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

   dialog_gauge
       implements the "--gauge" option.  Alternatively, a simpler or customized gauge widget  can
       be    setup   using   dlg_allocate_gauge,   dlg_reallocate_gauge,   dlg_update_gauge   and
       dlg_free_gauge.

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

       int percent
            is the percentage to show in the progress bar.

   dialog_inputbox
       implements the "--inputbox" or "--password" option, depending on the value of password.

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

       const char * init
            is the initial value of the input box, whose length is taken into account when  auto-
            sizing the width of the dialog box.

       int password
            if true, causes typed input to be echoed as asterisks.

   dialog_helpfile
       implements the "--hfile" option.

       const char * title
            is the title on the top of the widget.

       const char * file
            is  the  name  of a file containing the text to display.  This function is internally
            bound to F1 (function key "1"), passing dialog_vars.help_file as  a  parameter.   The
            dialog program sets that variable when the --hfile option is given.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

   dialog_menu
       implements    the    "--menu"    or    "--inputmenu"    option    depending   on   whether
       dialog_vars.input_menu is set.

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

       int menu_height
            is the minimum height to reserve for displaying the list.  If zero,  it  is  computed
            based on the given height and width.

       int item_no
            is the number of rows in items.

       int items
            is an array of strings which is viewed either as a list of rows
            tag item

            or
            tag item help

            depending on whether dialog_vars.item_help is set.

   dialog_mixedform
       implements the "--mixedform" option.

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is  the  desired  height  of  the  box.   If  zero, the height is adjusted to use the
            available screen size.

       int width
            is the desired width of the box.   If  zero,  the  height  is  adjusted  to  use  the
            available screen size.

       int form_height
            is  the  minimum  height to reserve for displaying the list.  If zero, it is computed
            based on the given height and width.

       int item_no
            is the number of rows in items.

       int items
            is an array of strings which is viewed either as a list of rows
            Name NameY NameX Text TextY TextX FLen ILen Ityp

            or
            Name NameY NameX Text TextY TextX FLen ILen Ityp Help

            depending on whether dialog_vars.item_help is set.

   dialog_mixedgauge
       implements the "--mixedgauge" option

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the caption text shown within the widget.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

       int percent
            is the percentage to show in the progress bar.

       int item_no
            is the number of rows in items.

       int items
            is an array of strings which is viewed as a list of tag and  item  values.   The  tag
            values are listed, one per row, in the list at the top of the widget.

            The item values are decoded: digits 0 through 9 are the following strings

            0      Succeeded

            1      Failed

            2      Passed

            3      Completed

            4      Checked

            5      Done

            6      Skipped

            7      In Progress

            8      (blank)

            9      N/A

            A  string  with  a  leading "-" character is centered, marked with "%".  For example,
            "-75" is displayed as "75%".  Other strings are displayed as is.

   dialog_msgbox
       implements the "--msgbox" or "--infobox" option depending on whether pauseopt is set.

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

       int pauseopt
            if true, an "OK" button will be shown, and the dialog will wait for it  to  complete.
            With  an "OK" button, it is denoted a "msgbox", without an "OK" button, it is denoted
            an "infobox".

   dialog_pause
       implements the "--pause" option.

       const char * title
            is the title on the top of the widget.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

       int seconds
            is the timeout to use for the progress bar.

   dialog_prgbox
       implements the "--prgbox" option.

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.  If empty or null, no prompt is shown.

       const char * command
            is the name of the command to execute.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

       int pauseopt
            if true, an "OK" button will be shown, and the dialog will wait for it to complete.

   dialog_progressbox
       implements the "--progressbox" option.

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.  If empty or null, no prompt is shown.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

   dialog_rangebox
       implements the "--rangebox" option.

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.  If empty or null, no prompt is shown.

       int height
            is the desired height of the widget.  If zero, the height  is  based  on  the  screen
            size.

       int width
            is the desired width of the widget.  If zero, the height is based on the screen size.

       int min_value
            is the minimum value to allow.

       int max_value
            is the maximum value to allow.

       int default_value
            is the default value, if no change is made.

   dialog_tailbox
       implements the "--tailbox" or "--tailboxbg" option depending on whether bg_task is set.

       const char * title
            is the title on the top of the widget.

       const char * file
            is the name of the file to display in the dialog.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

       int bg_task
            if  true,  the  window  is  added  to  the  callback  list  in  dialog_state, and the
            application will poll for the window to be updated.   Otherwise  an  "OK"  button  is
            added to the window, and it will be closed when the button is activated.

   dialog_textbox
       implements the "--textbox" option.

       const char * title
            is the title on the top of the widget.

       const char * file
            is the name of the file to display in the dialog.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

   dialog_timebox
       implements the "--timebox" option.

       const char * title
            is the title on the top of the widget.

       const char * subtitle
            is the prompt text shown within the widget.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

       int hour
            is  the  initial  hour  shown.   If  the value is negative, the current hour is used.
            Returns DLG_EXIT_ERROR if the value specified is greater than or equal to 24.

       int minute
            is the initial minute shown.  If the value is negative, the current minute  is  used.
            Returns DLG_EXIT_ERROR if the value specified is greater than or equal to 60.

       int second
            is  the  initial second shown.  If the value is negative, the current second is used.
            Returns DLG_EXIT_ERROR if the value specified is greater than or equal to 60.

   dialog_treeview
       implements the "--treeview" option.

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

       int list_height
            is the minimum height to reserve for displaying the list.  If zero,  it  is  computed
            based on the given height and width.

       int item_no
            is the number of rows in items.

       char ** items
            is   the  list  of  items,  contain  tag,  name,  and  optionally  help  strings  (if
            dialog_vars.item_help is set).  The initial selection state for each item is also  in
            this list.

       int flag

       flag is  either  FLAG_CHECK,  for  checklists  (multiple  selections),  or  FLAG_RADIO for
            radiolists (a single selection).

   dialog_yesno
       implements the "--yesno" option.

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

UTILITY FUNCTIONS

       Most functions that  implement  lower-level  functionality  for  the  command-line  dialog
       program  or  widgets,  have  names  beginning  "dlg_".   Bowing to longstanding usage, the
       functions that initialize the display and end it are named init_dialog and end_dialog.

       The only non-widget function whose name begins with  "dialog_"  is  dialog_version,  which
       returns the version number of the library as a string.

       Here is a brief summary of the utility functions and their parameters:

   dlg_add_callback
       Add a callback, used to allow polling input from multiple tailbox widgets.

       DIALOG_CALLBACK *p
            contains the callback information.

   dlg_add_callback_ref
       Like  dlg_add_callback, but passes a reference to the DIALOG_CALLBACK as well as a pointer
       to a cleanup function which will be called when the associated input ends.

       DIALOG_CALLBACK **p
            points to the callback information.  This is a reference to the pointer so  that  the
            caller's pointer can be zeroed when input ends.

       DIALOG_FREEBACK func
            function to call when input ends, e.g., to free caller's additional data.

   dlg_add_help_formitem
       This  is a utility function used enforce consistent behavior for the DIALOG_VARS.help_tags
       and DIALOG_VARS.item_help variables.

       int *result
            this is updated to DLG_EXIT_ITEM_HELP if DIALOG_VARS.item_help is set.

       char **tag
            the tag- or help-text is stored here.

       DIALOG_FORMITEM *item
            contains the list item to use for tag- or help-text.

   dlg_add_help_listitem
       This is a utility function used enforce consistent behavior for the  DIALOG_VARS.help_tags
       and DIALOG_VARS.item_help variables.

       int *result
            this is updated to DLG_EXIT_ITEM_HELP if DIALOG_VARS.item_help is set.

       char **tag
            the tag- or help-text is stored here.

       DIALOG_LISTITEM *item
            contains the list item to use for tag- or help-text.

   dlg_add_last_key
       Report  the  last  key  entered  by the user.  This implements the --last-key command-line
       option, using dialog_vars.last_key.

       int mode
            controls the way the last key report is separated from other results:

            -2   (no separator)

            -1   (separator after the key name)

            0    (separator is optionally before the key name)

            1    (same as -1)

   dlg_add_quoted
       Add a quoted string  to  the  result  buffer  (see  dlg_add_result).   If  no  quotes  are
       necessary,  none  are  used.  If dialog_vars.single_quoted is set, single-quotes are used.
       Otherwise, double-quotes are used.

       char * string
            is the string to add.

   dlg_add_result
       Add a string to the result buffer dialog_vars.input_result.

       char * string
            is the string to add.

   dlg_add_separator
       Add   an   output-separator   to   the   result   buffer   dialog_vars.input_result.    If
       dialog_vars.output_separator  is set, use that.  Otherwise, if dialog_vars.separate_output
       is set, use newline.  If neither is set, use a space.

   dlg_add_string
       Add  a  quoted  or  unquoted  string  to  the  result  buffer  (see  dlg_add_quoted)   and
       dlg_add_result), according to whether dialog_vars.quoted is true.

       char * string
            is the string to add.

   dlg_align_columns
       Copy  and  reformat  an  array  of  pointers  to strings, aligning according to the column
       separator dialog_vars.column_separator.  If no column separator is set, the array will  be
       unmodified; otherwise it is copied and reformatted.

              Caveat: This function is only implemented for 8-bit characters.

       char **target
            This is the array to reformat.  It points to the first string to modify.

       int per_row
            This is the size of the struct for each row of the array.

       int num_rows
            This is the number of rows in the array.

   dlg_allocate_gauge
       Allocates a gauge widget.  Use dlg_update_gauge to display the result.

       const char * title
            is the title string to display at the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is  the  desired  height  of  the  box.   If  zero, the height is adjusted to use the
            available screen size.

       int width
            is the desired width of the box.   If  zero,  the  height  is  adjusted  to  use  the
            available screen size.

       int percent
            is the percentage to show in the progress bar.

   dlg_asciibox
       returns  its  parameter  transformed  to  the corresponding "+" or "-", etc. for the line-
       drawing characters used in dialog.  If the  parameter  is  not  a  line-drawing  or  other
       special character such as ACS_DARROW, it returns 0.

       chtype ch
            is the parameter, usually one of the ACS_xxx constants.

   dlg_attr_clear
       Set window to the given attribute.

       WINDOW * win
            is the window to update.

       int height
            is the number of rows to update.

       int width
            is the number of columns to update.

       chtype attr
            is the attribute, e.g., A_BOLD.

   dlg_auto_size
       Automatically  size  the window used for a widget.  If the given height or width are zero,
       justify the prompt text and return the actual limits.

       const char * title
            is the title string to display at the top of the widget.

       const char * prompt
            is the message text which will be displayed in the widget, used here to determine how
            large the widget should be.

       int * height
            is the nominal height.

       int * width
            is the nominal width.

       int boxlines
            is the number of lines to reserve in the vertical direction.

       int mincols
            is the minimum number of columns to use.

   dlg_auto_sizefile
       Like dlg_auto_size, but use a file contents to decide how large the widget should be.

       const char * title
            is the title string to display at the top of the widget.

       const char * file
            is the name of the file.

       int * height
            is  the  nominal  height.   If  it  is -1, use the screen's height (after subtracting
            dialog_vars.begin_y if dialog_vars.begin_set is true).

       int * width
            is the nominal width.  If it  is  -1,  use  the  screen's  width  (after  subtracting
            dialog_vars.begin_x if dialog_vars.begin_set is true).

       int boxlines
            is the number of lines to reserve on the screen for drawing boxes.

       int mincols
            is the number of columns to reserve on the screen for drawing boxes.

   dlg_beeping
       If    dialog_vars.beep_signal    is    nonzero,    this   calls   beep   once   and   sets
       dialog_vars.beep_signal to zero.

   dlg_boxchar
       returns its chtype parameter transformed as follows:

       •   if neither dialog_vars.ascii_lines nor dialog_vars.no_lines is set.

       •   if dialog_vars.ascii_lines is set, returns the corresponding "+" or "-", etc. for  the
           line-drawing characters used in dialog.

       •   otherwise,  if  dialog_vars.no_lines  is  set,  returns  a  space for the line-drawing
           characters.

       •   if the parameter is not a line-drawing or other special character such as  ACS_DARROW,
           it returns the parameter unchanged.

   dlg_box_x_ordinate
       returns  a  suitable x-ordinate (column) for a new widget.  If dialog_vars.begin_set is 1,
       use dialog_vars.begin_x; otherwise center the  widget  on  the  screen  (using  the  width
       parameter).

       int width
            is the width of the widget.

   dlg_box_y_ordinate
       returns  a suitable y-ordinate (row) for a new widget.  If dialog_vars.begin_set is 1, use
       dialog_vars.begin_y;  otherwise  center  the  widget  on  the  screen  (using  the  height
       parameter).

       int height
            is the height of the widget.

   dlg_buildlist
       This  is  an  alternate  interface to the buildlist widget which allows the application to
       read the list item states back directly without putting them in the output buffer.

       const char * title
            is the title string to display at the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is the desired height of the box.  If  zero,  the  height  is  adjusted  to  use  the
            available screen size.

       int width
            is  the  desired  width  of  the  box.   If  zero,  the height is adjusted to use the
            available screen size.

       int list_height
            is the minimum height to reserve for displaying the list.  If zero,  it  is  computed
            based on the given height and width.

       int item_no
            is the number of rows in items.

       DIALOG_LISTITEM * items
            is   the  list  of  items,  contain  tag,  name,  and  optionally  help  strings  (if
            dialog_vars.item_help is set).  The initial selection state for each item is also  in
            this list.

       const char * states
            This  is  a list of characters to display for the given states.  Normally a buildlist
            provides true (1) and false (0) values, which the widget displays as "*"  and  space,
            respectively.   An application may set this parameter to an arbitrary null-terminated
            string.  The widget determines the number of states from the length of  this  string,
            and  will  cycle through the corresponding display characters as the user presses the
            space-bar.

       int order_mode
            is reserved for future enhancements

       int * current_item
            The widget sets the referenced location to the index  of  the  current  display  item
            (cursor) when it returns.

   dlg_button_count
       Count the buttons in the list.

       const char ** labels
            is a list of (pointers to) button labels terminated by a null pointer.

   dlg_button_layout
       Make  sure there is enough space for the buttons by computing the width required for their
       labels, adding margins and limiting based on the screen size.

       const char ** labels
            is a list of (pointers to) button labels terminated by a null pointer.

       int * limit
            the function sets the referenced limit to the width required for the buttons (limited
            by the screen size) if that is wider than the passed-in limit.

   dlg_button_sizes
       Compute the size of the button array in columns.

       const char ** labels
            is a list of (pointers to) button labels terminated by a null pointer.

       int vertical
            is true if the buttons are arranged in a column rather than a row.

       int * longest
            Return the total number of columns in the referenced location.

       int * length
            Return the longest button's columns in the referenced location.

   dlg_button_to_char
       Find the first uppercase character in the label, which we may use for an abbreviation.  If
       the label is empty, return -1.  If no uppercase character is found, return  0.   Otherwise
       return the uppercase character.

       Normally  dlg_draw_buttons  and  dlg_char_to_button  use  the  first  uppercase character.
       However, they keep track of all of the labels and if the first has already  been  used  in
       another  label, they will continue looking for another uppercase character.  This function
       does not have enough information to make that check.

       const char * label
            is the label to test.

   dlg_button_x_step
       Compute the step-size needed between elements of the button array.

       const char ** labels
            is a list of (pointers to) button labels terminated by a null pointer.

       int limit
            is the maximum number of columns to allow for the buttons.

       int * gap
            store  the  nominal  gap  between  buttons  in  the  referenced  location.   This  is
            constrained to be at least one.

       int * margin
            store  the  left+right  total  margins  (for  the  list of buttons) in the referenced
            location.

       int * step
            store the step-size in the referenced location.

   dlg_calc_list_width
       Calculate the minimum width for the list, assuming none of the items are truncated.

       int item_no
            is the number of items.

       DIALOG_LISTITEM * items
            contains a name and text field, e.g., for checklists or radiobox lists.  The function
            returns the sum of the widest columns needed for of each of these fields.

            If dialog_vars.no_items is set, the text fields in the list are ignored.

   dlg_calc_listh
       Calculate new height and list_height values.

       int * height
            on input, is the height without adding the list-height.  On return, this contains the
            total list-height and is the actual widget's height.

       int * list_height
            on input, is the requested list-height.  On return, this contains the number of  rows
            available  for  displaying the list after taking into account the screen size and the
            dialog_vars.begin_set and dialog_vars.begin_y variables.

       int item_no
            is the number of items in the list.

   dlg_calc_listw
       This function  is  obsolete,  provided  for  library-compatibility.   It  is  replaced  by
       dlg_calc_list_width.

       int item_no
            is the number of items.

       char ** items
            is a list of character pointers.

       int group
            is the number of items in each group, e.g., the second array index.

   dlg_char_to_button
       Given a list of button labels, and a character which may be the abbreviation for one, find
       it, if it exists.  An abbreviation will  be  the  first  character  which  happens  to  be
       capitalized  in the label.  If the character is found, return its index within the list of
       labels.  Otherwise, return DLG_EXIT_UNKNOWN.

       int ch
            is the character to find.

       const char ** labels
            is a list of (pointers to) button labels terminated by a null pointer.

   dlg_checklist
       This  entrypoint  provides  the  --checklist  or  --radiolist  functionality  without  the
       limitations of dialog's command-line syntax (compare to dialog_checklist).

       const char * title
            is the title string to display at the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is  the  desired  height  of  the  box.   If  zero, the height is adjusted to use the
            available screen size.

       int width
            is the desired width of the box.   If  zero,  the  height  is  adjusted  to  use  the
            available screen size.

       int list_height
            is  the  minimum  height to reserve for displaying the list.  If zero, it is computed
            based on the given height and width.

       int item_no
            is the number of items.

       DIALOG_LISTITEM * items
            This is a list of the items to display in the checklist.

       const char * states
            This is a list of characters to display for the given states.  Normally  a  checklist
            provides  true  (1) and false (0) values, which the widget displays as "*" and space,
            respectively.  An application may set this parameter to an arbitrary  null-terminated
            string.   The  widget determines the number of states from the length of this string,
            and will cycle through the corresponding display characters as the user  presses  the
            space-bar.

       int flag
            This  is  should  be one of FLAG_CHECK or FLAG_RADIO, depending on whether the widget
            should act as a checklist or radiobox.

       int * current_item
            The widget sets the referenced location to the index  of  the  current  display  item
            (cursor) when it returns.

   dlg_check_scrolled
       given  a function key (or other key that was mapped to a function key), check if it is one
       of the up/down scrolling functions:

              DLGK_PAGE_FIRST,
              DLGK_PAGE_LAST,
              DLGK_GRID_UP,
              DLGK_GRID_DOWN,
              DLGK_PAGE_PREV or
              DLGK_PAGE_NEXT.

       Some widgets use these key bindings for scrolling the prompt-text up and  down,  to  allow
       for display in very small windows.

       The function returns 0 (zero) if it finds one of these keys, and -1 if not.

       int key
            is the function-key to check

       int last
            is  the  number  of  lines  which  would be used to display the scrolled prompt in an
            arbitrarily tall window.  It is used here to check limits for the offset value.

       int page
            this is the available height for writing scrolled text, which  is  smaller  than  the
            window if it contains buttons.

       bool * show
            on  return,  holds  TRUE if dlg_print_scrolled should be used to redisplay the prompt
            text.

       int * offset
            on entry, holds  the  starting  line  number  (counting  from  zero)  last  used  for
            dlg_print_scrolled.  On return, holds the updated starting line number.

   dlg_clear
       Set  window  to  the  default  dialog  screen  attribute.  This is set in the rc-file with
       screen_color.

   dlg_clr_result
       Free storage used for the result  buffer  (dialog_vars.input_result).   The  corresponding
       pointer is set to NULL.

   dlg_color_count
       Return the number of colors that can be configured in dialog.

   dlg_color_setup
       Initialize the color pairs used in dialog.

   dlg_count_argv
       Count the entries in an argument vector.

       argv Points to the argument vector.

   dlg_count_columns
       Returns  the  number  of columns used for a string.  This is not necessarily the number of
       bytes in a string.

       const char * string
            is the string to measure.

   dlg_count_real_columns
       Returns the number of columns used for a string, accounting for "\Z" sequences  which  can
       be  used  for coloring the text if dialog_vars.colors is set.  This is not necessarily the
       number of bytes in a string.

       const char * string
            is the string to measure.

   dlg_count_wchars
       Returns the number of wide-characters in the string.

       const char * string
            is the string to measure.

   dlg_create_rc
       Create a configuration file, i.e., write internal tables to a file which can be read  back
       by dialog as an rc-file.

       const char * filename
            is the name of the file to write to.

   dlg_ctl_size
       If dialog_vars.size_err is true, check if the given window size is too large to fit on the
       screen.  If so, exit with an error reporting the size of the window.

       int height
            is the window's height

       int width
            is the window's width

   dlg_default_button
       If dialog_vars.default_button is positive, return the button-index for that  button  code,
       using dlg_ok_buttoncode to test indices starting with zero.  Otherwise (or if no match was
       found for the button code), return zero.

   dlg_default_formitem
       If dialog_vars.default_item is not null, find that name by matching the name field in  the
       list  of  form  items.   If  found, return the index of that item in the list.  Otherwise,
       return zero.

       DIALOG_FORMITEM * items
            is the list of items to search.  It is terminated by an entry with a null name field.

   dlg_default_item
       This function  is  obsolete,  provided  for  library-compatibility.   It  is  replaced  by
       dlg_default_formitem and dlg_default_listitem.

       char ** items
            is the list of items to search.

       int llen
            is the number of items in each group, e.g., the second array index.

   dlg_defaultno_button
       If  dialog_vars.defaultno  is true, and dialog_vars.nocancel is not, find the button-index
       for the "Cancel" button.  Otherwise, return the index for "OK" (always zero).

   dlg_del_window
       Remove a window, repainting everything else.

       WINDOW * win
            is the window to remove.

   dlg_does_output
       This is called each time  a  widget  is  invoked  which  may  do  output.   It  increments
       dialog_state.output_count,  so  the  output  function  in  dialog  can test this and add a
       separator.

   dlg_draw_arrows
       Draw up/down arrows on a window, e.g., for scrollable lists.   It  calls  dlg_draw_arrows2
       using the menubox_color and menubox_border_color attributes.

       WINDOW * dialog
            is the window on which to draw an arrow.

       int top_arrow
            is true if an up-arrow should be drawn at the top of the window.

       int bottom_arrow
            is true if an down-arrow should be drawn at the bottom of the window.

       int x
            is the zero-based column within the window on which to draw arrows.

       int top
            is  the  zero-based  row  within  the  window on which to draw up-arrows as well as a
            horizontal line to show the window's top.

       int bottom
            is the zero-based row within the window on which to draw down-arrows  as  well  as  a
            horizontal line to show the window's bottom.

   dlg_draw_arrows2
       Draw up/down arrows on a window, e.g., for scrollable lists.

       WINDOW * dialog
            is the window on which to draw an arrow.

       int top_arrow
            is true if an up-arrow should be drawn at the top of the window.

       int bottom_arrow
            is true if an down-arrow should be drawn at the bottom of the window.

       int x
            is the zero-based column within the window on which to draw arrows.

       int top
            is  the  zero-based  row  within  the  window on which to draw up-arrows as well as a
            horizontal line to show the window's top.

       int bottom
            is the zero-based row within the window on which to draw down-arrows  as  well  as  a
            horizontal line to show the window's bottom.

       chtype attr
            is the window's background attribute.

       chtype borderattr
            is the window's border attribute.

   dlg_draw_bottom_box
       Draw  a  partial box at the bottom of a window, e.g., to surround a row of buttons.  It is
       designed to merge with an existing box around the whole window (see dlg_draw_box),  so  it
       uses tee-elements rather than corner-elements on the top corners of this box.

       WINDOW * win
            is the window to update.

   dlg_draw_bottom_box2
       Draw  a  partial box at the bottom of a window, e.g., to surround a row of buttons.  It is
       designed to merge with an existing box around the whole window (see dlg_draw_box2), so  it
       uses tee-elements rather than corner-elements on the top corners of this box.

       WINDOW * win
            is the window to update.

       chtype on_left
            is  used  to  color  the  upper/left  edges  of  the  box,  i.e., the tee-element and
            horizontal line

       chtype on_right
            is used to color the right edge of the box, i.e., the tee-element

       chtype on_inside
            is used to fill-color the inside of the box

   dlg_draw_box
       Draw a rectangular box with line drawing characters.

       WINDOW * win
            is the window to update.

       int y
            is the top row of the box.

       int x
            is the left column of the box.

       int height
            is the height of the box.

       int width
            is the width of the box.

       chtype boxchar
            is used to color the right/lower edges.  It also  is  fill-color  used  for  the  box
            contents.

       chtype borderchar
            is used to color the upper/left edges.

   dlg_draw_box2
       Draw a rectangular box with line drawing characters.

       WINDOW * win
            is the window to update.

       int y
            is the top row of the box.

       int x
            is the left column of the box.

       int height
            is the height of the box.

       int width
            is the width of the box.

       chtype boxchar
            is used to fill-color for the box contents.

       chtype borderchar
            is used to color the upper/left edges.

       chtype borderchar2
            is used to color the right/lower edges.

   dlg_draw_buttons
       Print a list of buttons at the given position.

       WINDOW * win
            is the window to update.

       int y
            is the starting row.

       int x
            is the starting column.

       const char ** labels
            is a list of (pointers to) button labels terminated by a null pointer.

       int selected
            is the index within the list of the selected button.

       int vertical
            is true if the buttons are arranged in a column rather than a row.

       int limit
            is the number of columns (or rows if vertical) allowed for the display.

   dlg_draw_helpline
       draw the text in dialog_vars.help_line at the bottom of the given window.

       WINDOW * dialog
            is the window to modify.

       bool decorations
            if true, allow room for the scrolling arrows.

   dlg_draw_scrollbar
       If  dialog_state.use_scrollbar  is  set,  draw  a scrollbar on the right margin of windows
       holding scrollable data.  Also (whether or not  the  scrollbar  is  drawn),  annotate  the
       bottom  margin of the window with the percentage of data by the bottom of that window, and
       call dlg_draw_arrows2 to put markers on the window showing when more data is available.

       WINDOW * win
            is the window in which the data is scrolled.  Because left, right,  top,  bottom  are
            passed as parameters, this window can contain additional data.

       long first_data
            is the zero-based index to the first row of data in the current window.

       long this_data
            is the zero-based index to the current row of data.

       long next_data
            is the zero-based index to the next data after the current row.

       long total_data
            is the total number of rows of data.

       int left
            is  the  zero-based  left  margin/column  of the window.  The up/down arrows are draw
            inset by 5 columns from this point.

       int right
            is the zero-based right margin/column of the window.  The scrollbar  is  drawn  flush
            against this column.

       int top
            is  the  zero-based  row  within  the  window on which to draw up-arrows as well as a
            horizontal line to show the window's top.

       int bottom
            is the zero-based row within the window on which to draw down-arrows  as  well  as  a
            horizontal line to show the window's bottom.

       chtype attr
            is the window's background attribute.

       chtype borderattr
            is the window's border attribute.

   dlg_draw_shadow
       Draw  shadows along the right and bottom edge of a window to give it a 3-dimensional look.
       (The height, etc., may not be the same as the window's actual values).

       WINDOW * win
            is the window to update.

       int height
            is the height of the window.

       int width
            is the width of the window.

       int y
            is the top row of the window.

       int x
            is the left column of the window.

   dlg_draw_title
       Draw a title centered at the top of the window.

       WINDOW * win
            is the window to update.

       const char * title
            is the title string to display at the top of the widget.

   dlg_dummy_menutext
       This is a utility function which supports the --inputmenu option of  the  dialog  program.
       If  dialog_vars.input_menu  is  set,  dialog_menu  passes  this pointer to dlg_menu as the
       rename_menutext parameter.  Otherwise, it passes dlg_dummy_menutext.

       The function should only return DLG_EXIT_ERROR.

       DIALOG_LISTITEM * items
            is the list of menu items

       int current
            is the index of the currently-selected item

       char * newtext
            is the updated text for the menu item

   dlg_dump_keys
       Write all user-defined key-bindings to the given stream, e.g., as part of dlg_create_rc.

       FILE * fp
            is the stream on which to write the bindings.

   dlg_dump_window_keys
       Write all user-defined key-bindings to the given stream, e.g., as part of dlg_create_rc.

       FILE * fp
            is the stream on which to write the bindings.

       WINDOW * win
            is the window for which bindings should be dumped.  If it is null, then only built-in
            bindings are dumped.

   dlg_eat_argv
       Remove one or more items from an argument vector.

       int * argcp
            in/out  parameter  giving  the  length of the argument vector.  char *** argvp in/out
            parameter pointing to the argument vector.  int  start  starting  index.   int  count
            number of arguments to remove.

   dlg_edit_offset
       Given  the  character-offset in the string, returns the display-offset where dialog should
       position the cursor.  In this context, "characters" may be multicolumn, since  the  string
       can be a multibyte character string.

       char * string
            is the string to analyze

       int offset
            is the character-offset

       int x_last
            is a limit on the column positions that can be used, e.g., the window's size.

   dlg_edit_string
       Updates  the  string  and  character-offset,  given  various editing characters or literal
       characters which are inserted at the character-offset.  Returns true if an editing  change
       was  made  (and  the  display  should be updated), and false if the key was something like
       KEY_ENTER, which is a non-editing action outside this function.

       char * string
            is the (multibyte) string to update

       int * offset
            is the character-offset

       int key
            is the editing key

       int fkey
            is true if the editing key is a function-key

       bool force
            is used in a special loop case by calling code to force  the  return  value  of  this
            function when a function-key code 0 is passed in.

   dlg_exit
       Given  an  internal exit code, check if the corresponding environment variable is set.  If
       so, remap the exit code to match the environment variable.  Finally  call  exit  with  the
       resulting exit code.

       int code
            is the internal exit code, e.g., DLG_EXIT_OK, which may be remapped.

       The  dialog  program  uses this function to allow shell scripts to remap the exit codes so
       they can distinguish ESC from ERROR.

   dlg_exit_buttoncode
       Map the given button index for dlg_exit_label into dialog's exit-code.

       int button
            is the button index

   dlg_exit_label
       Return a list of button labels.  If dialog_vars.extra_button is true, return the result of
       dlg_ok_labels.    Otherwise,   return   a   list   with   the   "Exit"   label   and   (if
       dialog_vars.help_button is set) the "Help" button as well.

   dlg_exiterr
       Quit program killing all tailboxbg widgets.

       const char * fmt
            is the format of the printf-like message to write.

       ...
            are the variables to apply to the fmt format.

   dlg_find_index
       Given the character-offset to find in the list, return the corresponding array index.

       const int *list
            contains a list of character-offsets, i.e., indices into a  string  that  denote  the
            beginning of multibyte characters.

       int limit
            is the last index into list to search.

       int to_find
            is the character-offset to find.

   dlg_finish_string
       If DIALOG_STATE.finish_string is true, this function discards data used to speed up layout
       computations.

       const char * string
            is the address of the string whose data should be discarded.  The address rather than
            contents  is  used  as  the unique identifier because some of the caching is used for
            editable input-fields.

   dlg_flush_getc
       Cancel the local data saved by dlg_last_getc.

   dlg_editbox
       This entrypoint provides the --editbox functionality without the limitations  of  dialog's
       command-line syntax (compare to dialog_editbox).

       const char * title
            is the title string to display at the top of the widget.

       char *** list
            is  a  pointer to an array of char * pointers.  The array is allocated by the caller,
            and so are the strings to which it points.  The dlg_editbox function  may  reallocate
            the array and the strings.

       int * rows
            points  to  the  nominal  length  of list.  The referenced value is updated iflist is
            reallocated.

       int height
            is the desired height of the box.  If  zero,  the  height  is  adjusted  to  use  the
            available screen size.

       int width
            is  the  desired  width  of  the  box.   If  zero,  the height is adjusted to use the
            available screen size.

   dlg_form
       This entrypoint provides the --form functionality  without  the  limitations  of  dialog's
       command-line syntax (compare to dialog_form).

       const char * title
            is the title string to display at the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is  the  desired  height  of  the  box.   If  zero, the height is adjusted to use the
            available screen size.

       int width
            is the desired width of the box.   If  zero,  the  height  is  adjusted  to  use  the
            available screen size.

       int form_height
            is  the  minimum  height to reserve for displaying the list.  If zero, it is computed
            based on the given height and width.

       int item_no
            is the number of items.

       DIALOG_FORMITEM * items
            This is a list of the items to display in the form.

       int * current_item
            The widget sets the referenced location to the index  of  the  current  display  item
            (cursor) when it returns.

   dlg_free_columns
       Free data allocated by dlg_align_columns.

       char **target
            This is the array which was reformatted.  It points to the first string to free.

       int per_row
            This is the size of the struct for each row of the array.

       int num_rows
            This is the number of rows in the array.

   dlg_free_formitems
       Free memory owned by a list of DIALOG_FORMITEM's.

       DIALOG_FORMITEM * items
            is the list to free.

   dlg_free_gauge
       Remove the gauge widget from the screen and free its associated memory.

       void *objptr
            points to the gauge widget.

   dlg_getc
       Read a character from the given window.  Handle repainting here (to simplify things in the
       calling application).  Also, if input-callback(s) are set up, poll the corresponding files
       and handle the updates, e.g., for displaying a tailbox.  Returns the key-code.

       WINDOW * win
            is the window within which to read.

       int * fkey
            as a side-effect, set this to true if the key-code is really a function-key.

   dlg_get_attrs
       extract the video attributes from the given window.

       WINDOW * win
            is the window from which to get attributes.

   dlg_getc_callbacks
       passes  the  given  key-code ch to the current window that has established a callback.  If
       the callback returns zero, remove it and try  the  next  window.   If  no  more  callbacks
       remain, return.  If any callbacks were found, return true, otherwise false.

       int ch
            is the key-code

       int fkey
            is true if the key is a function-key

       int * result
            is used to pass an exit-code to the caller, which should pass that via dlg_exit.

   dlg_index_columns
       Build a list of the display-columns for the given multibyte string's characters.

       const char * string
            is the string to analyze

   dlg_index_wchars
       Build  an  index of the wide-characters in the string, so the caller can easily tell which
       byte-offset begins a given wide-character.

       const char * string
            is the string to analyze

   dlg_item_help
       Draw the string for the dialog_vars.item_help feature.

       const char * txt
            is the help-message

   dlg_killall_bg
       If dialog has callbacks active, purge the list of all that are not marked to keep  in  the
       background.  If any remain, run those in a background process.

       int * retval
            stores the exit-code to pass back to the caller.

   dlg_last_getc
       returns the most recent character that was read via dlg_getc.

   dlg_limit_columns
       Given  a  column  limit, count the number of wide characters that can fit into that limit.
       The offset is used to skip over a leading character that was already written.

       const char * string
            is the string to analyze

       int limit
            is the column limit

       int offset
            is the starting offset from which analysis should continue

   dlg_lookup_key
       Check for a key-binding.  If there is no binding associated with  the  widget,  it  simply
       returns the given curses-key.  Otherwise, it returns the result of the binding

       WINDOW * win
            is the window on which the binding is checked

       int curses_key
            is the curses key-code

       int * dialog_key
            is the corresponding dialog internal code (see DLG_KEYS_ENUM in dlg_key.h).

   dlg_max_input
       Limit the parameter according to dialog_vars.max_input

       int max_len
            is the value to limit

   dlg_match_char
       Match  a  given  character against the beginning of the string, ignoring case of the given
       character.  The matching string must begin with an uppercase character.

       int ch
            is the character to check

       const char * string
            is the string to search

   dlg_menu
       This entrypoint provides the --menu functionality  without  the  limitations  of  dialog's
       command-line syntax (compare to dialog_menu).

       const char * title
            is the title string to display at the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is  the  desired  height  of  the  box.   If  zero, the height is adjusted to use the
            available screen size.

       int width
            is the desired width of the box.   If  zero,  the  height  is  adjusted  to  use  the
            available screen size.

       int menu_height
            is  the  minimum  height to reserve for displaying the list.  If zero, it is computed
            based on the given height and width.

       int item_no
            is the number of items.

       DIALOG_LISTITEM * items
            This is a list of the items to display in the form.

       int * current_item
            The widget sets the referenced location to the index  of  the  current  display  item
            (cursor) when it returns.

       DIALOG_INPUTMENU rename_menutext
            If  this  is  not  dlg_dummy_menutext,  the  widget  acts  like  an inputmenu widget,
            providing an extra "Rename" button, which activates an edit feature on  the  selected
            menu item.

   dlg_move_window
       Moves/resizes the given window to the given position and size.

       WINDOW *win
            is the window to move/resize.

       WINDOW *height
            is the height of the resized window.

       WINDOW *width
            is the width of the resized window.

       WINDOW *y
            y-ordinate to use for the repositioned window.

       WINDOW *x
            x-ordinate to use for the repositioned window.

   dlg_mouse_bigregion
       Retrieve the big-region under the pointer.

       int y
            is the row on which the mouse click occurred

       int x
            is the column on which the mouse click occurred

   dlg_mouse_free_regions
       Free the memory associated with mouse regions.

   dlg_mouse_mkbigregion
       Creates a region on which the mouse-clicks will return a specified code.

       int y
            is the top-row of the region.

       int x
            is the left-column of the region.

       int height
            is the height of the region.

       int width
            is the width of the region.

       int code
            is a code used to make the region unique within a widget

       int step_x
            is used in modes 2 (columns) and 3 (cells) to determine the width of a column/cell.

       int step_y
            is currently unused

       int mode
            is  used  to  determine  how  the  mouse  position  is translated into a code (like a
            function-key):

            1  index by lines

            2  index by columns

            3  index by cells

   dlg_mouse_mkregion
       int y
            is the top-row of the region.

       int x
            is the left-column of the region.

       int height
            is the height of the region.

       int width
            is the width of the region.

       int code
            is a code used to make the region unique within a widget

   dlg_mouse_region
       Retrieve the frame under the mouse pointer

       int y
            is the row of the mouse-click

       int x
            is the column of the mouse-click

   dlg_mouse_setbase
       Sets a base for subsequent calls to dlg_mouse_mkregion, so they can make regions  relative
       to the start of a given window.

       int x
            is the left-column for the base

       int y
            is the top-row for the base

   dlg_mouse_setcode
       Sets  a  value used internally by dlg_mouse_mkregion which is added to the code parameter.
       By providing different values, e.g., multiples of  KEY_MAX,  it  is  possible  to  support
       multiple  "big"  regions in a widget.  The buildlist widget uses this feature to recognize
       mouse-clicks in the left/right panes.

       int code
            is the value to add to dlg_mouse_mkregion's code parameter.

   dlg_mouse_wgetch
       is a wrapper for dlg_getc which additionally maps  mouse-clicks  (if  the  curses  library
       supports  those)  into  extended  function-keys which encode the position according to the
       mode in dlg_mouse_mkbigregion.  Returns the corresponding key-code.

       WINDOW * win
            is the window on which to perform the input

       int * fkey
            the referenced location is set to true if the  key-code  is  an  actual  or  extended
            (mouse) function-key.

   dlg_mouse_wgetch_nowait
       This is a non-blocking variant of dlg_mouse_wgetch.

       WINDOW * win
            is the window on which to perform the input

       int * fkey
            the  referenced  location  is  set  to  true if the key-code is an actual or extended
            (mouse) function-key.

   dlg_need_separator
       Check if an output-separator is needed.  If dialog_vars.output_separator  is  set,  return
       true.   Otherwise,  if  dialog_vars.input_result  is  nonempty,  return true.  If neither,
       return false.

   dlg_new_modal_window
       Create  a  modal  window,  optionally  with  a  shadow.   The   shadow   is   created   if
       dialog_state.use_shadow is true.

       WINDOW * parent
            is the parent window (usually the top-level window of a widget)

       int height
            is the window's height

       int width
            is the window's width

       int y
            is the window's top-row

       int x
            is the window's left-column

   dlg_new_window
       Create   a   window,   optionally   with   a   shadow.    The   shadow   is   created   if
       dialog_state.use_shadow is true.

       int height
            is the window's height

       int width
            is the window's width

       int y
            is the window's top-row

       int x
            is the window's left-column

   dlg_next_button
       Return the next index in the list of labels.

       const char ** labels
            is a list of (pointers to) button labels terminated by a null pointer.

       int button
            is the current button-index.

   dlg_next_ok_buttonindex
       Assuming that the caller is using dlg_ok_labels to list buttons, find the  next  index  in
       the list of buttons.

       int current
            is the current index in the list of buttons

       int extra
            if negative, provides a way to enumerate extra active areas on the widget.

   dlg_ok_buttoncode
       Map the given button index for dlg_ok_labels into dialog's exit-code.

       int button
            is  the  button-index  (which is not necessarily the same as the index in the list of
            labels).

   dlg_ok_label
       Returns a list with the "Ok" label, and if dialog_vars.help_button  is  true,  the  "Help"
       label as well.

   dlg_ok_labels
       Return a list of button labels for the OK/Cancel group of widgets.

   dlg_ordinate
       Decode  the string as an integer, decrement if greater than zero to make a curses-ordinate
       from a dialog-ordinate.

   dlg_parse_bindkey
       Parse the parameters of the "bindkeys" configuration-file entry.  This expects widget name
       which may be "*", followed by curses key definition and then dialog key definition.

       char * params
            is the parameter string to parse.

   dlg_parse_rc
       Parse the configuration file and set up variables.

   dlg_popen
       Open  a  pipe  which  ties  the  standard  error  and output together.  The popen function
       captures only the standard output of a command.

       const char *command
            The shell command to run.

       const char *type
            Like popen, "r" is used to read, and "w" is used to write.

   dlg_prev_button
       Return the previous index in the list of labels.

       const char ** labels
            is a list of (pointers to) button labels terminated by a null pointer.

       int button
            is the current button index

   dlg_print_listitem
       This is a helper function used for the various  "list"  widgets,  e.g.,  checklist,  menu,
       buildlist,  treeview.   Each  list-widget has "tag" and "description" values for each item
       which can be displayed.  If dialog_vars.no_tags is true, the "tag"  value  is  not  shown.
       The  first  character  of  the  first  value  shown (tag or description) is highlighted to
       indicate that the widget will match it for quick navigation.

       WINDOW *win
            the window in which to display the text

       const char *text
            the value to display

       int climit
            the number of columns available for printing the text

       bool first
            true if this is the first call (for "tag" and "description"), and the first character
            of the value should be highlighted.

       int selected
            nonzero if the text should be displayed using the "selected" colors

   dlg_print_scrolled
       This  is  a wrapper for dlg_print_autowrap which allows the user to scroll too-long prompt
       text up/down.

       See dlg_check_scrolled for a  function  which  updates  the  offset  variable  used  as  a
       parameter  here.   It  complements this function; you need both.  If pauseopt is set, this
       function returns an updated last parameter, needed for dlg_check_scrolled calls.

       WINDOW * win
            is the window to update.

       const char * prompt
            is the string to print

       int offset
            is the starting line-number to write wrapped text.

       int height
            is the available height for writing the wrapped text

       int width
            is the width that the wrapping should occur in

       int pauseopt
            is true if the extra functionality for scrolling should be enabled.  If  false,  this
            calls dlg_print_autowrap without doing any scrolling.

   dlg_print_line
       Print  one  line  of  the  prompt  in  the window within the limits of the specified right
       margin.  The line will end on a word boundary and a pointer to the start of the next  line
       is returned, or a NULL pointer if the end of *prompt is reached.

       WINDOW *win
            is the window to update.

       chtype *attr
            holds the starting attributes, and is updated to reflect the final attributes applied
            to the string.

       const char *prompt
            is the string to print

       int lm
            is the left margin.

       int rm
            is the right margin

       int *x
            returns the ending x-ordinate.

   dlg_prev_ok_buttonindex
       Find the previous button index in the list from dlg_ok_labels.

       int current
            is the current index

       int extra
            if negative provides a way to enumerate extra active areas on the widget.

   dlg_print_autowrap
       Print a string of text in a window, automatically wrap around to  the  next  line  if  the
       string  is  too  long  to  fit  on  one  line.   Note that the string may contain embedded
       newlines.  The text is written starting at the top of the window.

       WINDOW * win
            is the window to update.

       const char * prompt
            is the string to print

       int height
            is the nominal height the wrapped string is limited to

       int width
            is the width that the wrapping should occur in

   dlg_print_size
       If dialog_vars.print_siz is  true,  print  the  given  height/width  (from  a  widget)  to
       dialog_state.output, e.g., Size: height, width.

       int height
            is the window's height

       int width
            is the window's width

   dlg_print_text
       Print  up  to  cols  columns from text, optionally rendering dialog's escape sequences for
       attributes and color.

       WINDOW * win
            is the window to update.

       const char * txt
            is the string to print

       int col
            is the column limit

       chtype * attr
            holds the starting attributes, and is updated to reflect the final attributes applied
            to the string.

   dlg_progressbox
       implements the "--prgbox" and "--progressbox" options.

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.  If empty or null, no prompt is shown.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

       int pauseopt
            if  true,  an "OK" button will be shown, and the dialog will wait for it to complete.
            With an "OK" button, it is denoted a "programbox", without  an  "OK"  button,  it  is
            denoted a "progressbox".

       FILE * fp
            is the file pointer, which may be a pipe or a regular file.

   dlg_put_backtitle
       Display  the  background title if dialog_vars.backtitle is non-null.  The background title
       is shown at the top of the screen.

   dlg_reallocate_gauge
       Allocates or reallocates a gauge widget (see dlg_allocate_gauge).  Use dlg_update_gauge to
       display the result.

       void ** objptr
            If the pointer referenced by this parameter is null, the function creates a new gauge
            widget using dlg_allocate_gauge.  Otherwise, it updates the title and cprompt values,
            reusing  the  window  from the previous call on this function.  As a side-effect, the
            function stores the updated object-pointer via the objptr parameter.

       const char * title
            is the title string to display at the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is the desired height of the box.  If  zero,  the  height  is  adjusted  to  use  the
            available screen size.

       int width
            is  the  desired  width  of  the  box.   If  zero,  the height is adjusted to use the
            available screen size.

       int percent
            is the percentage to show in the progress bar.

   dlg_register_buttons
       The widget developer should call this function after dlg_register_window, for the list  of
       button  labels associated with the widget.  One may bind a key to a button, e.g., "OK" for
       DLGK_OK,

       WINDOW * win
            is the window with which to associate the buttons

       const char * name
            is the widget's binding name (usually the name of the widget).

       const char ** buttons
            is the list of buttons

   dlg_register_window
       For a given named widget's window, associate a binding table.

       WINDOW * win
            is the window with which to associate the buttons

       const char * name
            is the widget's binding name (usually the name of the widget).

       DLG_KEYS_BINDING * binding
            is the binding table

   dlg_remove_callback
       Remove a callback.

       DIALOG_CALLBACK * p
            contains the callback information.

   dlg_renamed_menutext
       This is a utility function which supports the --inputmenu option of  the  dialog  program.
       If  dialog_vars.input_menu  is  set,  dialog_menu  passes  this pointer to dlg_menu as the
       rename_menutext parameter.  Otherwise, it passes dlg_dummy_menutext.

       The function should add "RENAMED" to  dialog_vars.input_result  ,  followed  by  the  menu
       item's  name  and  the newtext value (with a space separating the three items), and return
       DLG_EXIT_EXTRA.

       DIALOG_LISTITEM * items
            is the list of menu items

       int current
            is the index of the currently-selected item

       char * newtext
            is the updated text for the menu item

   dlg_restore_vars
       Restore dialog's variables from the given variable (see dialog_save_vars).

       DIALOG_VARS * save
            is the variable from which to restore.

       The DIALOG_VARS.input_length and DIALOG_VARS.input_result members are  treated  specially,
       since  these  are  used  by a widget to pass data to the caller.  They are not modified by
       this function.

   dlg_result_key
       Test a dialog internal keycode to see if it corresponds to one of the push buttons on  the
       widget  such  as  "OK".  This is only useful if there are user-defined key bindings, since
       there are no built-in bindings that map directly  to  DLGK_OK,  etc.   Return  true  if  a
       mapping was done.

       int dialog_key
            is the dialog key to test

       int fkey
            is true if this is a function key

       int * resultp
            store the result of the mapping in the referenced location.

   dlg_save_vars
       Save dialog's variables into the given variable (see dlg_restore_vars).

       DIALOG_VARS * save
            is the variable into which to save.

   dlg_set_focus
       Set focus on the given window, making it display above other windows on the screen.

       WINDOW * parent
            is the parent window (usually the top-level window of a widget)

       WINDOW * win
            is the window on which to place focus (usually a subwindow of a widget)

   dlg_set_result
       Setup a fixed-buffer for the result in dialog_vars.input_result

       const char * string
            is the new contents for the result

   dlg_show_string
       Displays  the  string,  shifted  as  necessary, to fit within the box and show the current
       character-offset.

       WINDOW * win
            is the window within which to display

       const char * string
            is the string to display

       int offset
            is the starting (character, not bytes) offset

       chtype attr
            is the window attribute to use for the string

       int y_base
            beginning row on screen

       int x_base
            beginning column on screen

       int x_last
            number of columns on screen

       bool hidden
            if true, do not echo input

       bool force
            if true, force repaint

   dlg_strclone
       duplicate the string, like strdup.

       const char * cprompt
            is the string to duplicate

   dlg_strcmp
       compare two strings, ignoring case.

       const char * a
            is one string

       const char * b
            is the other string

   dlg_string_to_argv
       Convert a string to an argument vector returning an index (which  must  be  freed  by  the
       caller).  The string is modified (replacing gaps between tokens with nulls).

       char *blob
            is the string to convert.

   dlg_sub_window
       create a subwindow, e.g., for an input area of a widget

       WINDOW * win
            is the parent window

       int height
            is the subwindow's height

       int width
            is the subwindow's width

       int y
            is the subwindow's top-row

       int x
            is the subwindow's left-column

   dlg_tab_correct_str
       If  the  dialog_vars.tab_correct  is  true,  convert  tabs  to  single spaces.  Return the
       converted result.  The caller is responsible for freeing the string.

       char * prompt
            is the string to convert

   dlg_trace
       If the parameter is non-null, opens a trace file  with  that  name  and  stores  the  file
       pointer in dialog_state.trace.

   dlg_trace_chr
       If  dialog_state.trace  is  set, translate the parameters into a printable representation,
       log it on a "chr" line.

       int ch
            is the nominal keycode value.

       int fkey
            is nonzero if the value is really a function  key.   Some  of  these  may  be  values
            declared in the DLG_KEYS_ENUM.

   dlg_trace_msg
       Write a formatted message to the trace file.

       const char * fmt
            is the format of the printf-like message to write.

       ...
            are the variables to apply to the fmt format.

       Use  the  DLG_TRACE  macro for portability, in case the trace feature is not compiled into
       the library.  It uses an extra level of parentheses to work  with  a  variable  number  of
       parameters, e.g.,

              DLG_TRACE(("this is dialog version %s\n", dialog_version()));

   dlg_trace_win
       If dialog_state.trace is set, log a printable picture of the given window.

   dlg_treeview
       This is an alternate interface to 'treeview' which allows the application to read the list
       item states back directly without putting them in the output buffer.

       const char * title
            is the title on the top of the widget.

       const char * cprompt
            is the prompt text shown within the widget.

       int height
            is the desired height of the box.  If zero, the height is based on the screen size.

       int width
            is the desired width of the box.  If zero, the height is based on the screen size.

       int list_height
            is the minimum height to reserve for displaying the list.  If zero,  it  is  computed
            based on the given height and width.

       int item_no
            is the number of rows in items.

       DIALOG_LISTITEM * items
            is   the  list  of  items,  contain  tag,  name,  and  optionally  help  strings  (if
            dialog_vars.item_help is set).  The initial selection state for each item is also  in
            this list.

       const char * states
            This  is  a list of characters to display for the given states.  Normally a buildlist
            provides true (1) and false (0) values, which the widget displays as "*"  and  space,
            respectively.   An application may set this parameter to an arbitrary null-terminated
            string.  The widget determines the number of states from the length of  this  string,
            and  will  cycle through the corresponding display characters as the user presses the
            space-bar.

       int * depths
            This is a list of depths of each item in the tree.  It is a separate  parameter  from
            items to allow reuse of the existing functions.

       int flag
            is  either  FLAG_CHECK,  for  checklists  (multiple  selections),  or  FLAG_RADIO for
            radiolists (a single selection).

       int * current_item
            The widget sets the referenced location to the index  of  the  current  display  item
            (cursor) when it returns.

   dlg_trim_string
       The  dialog  program  uses  this  in  each  widget to adjust the message string, which may
       contain the newline character (referred to as '\n')  and/or  the  special  substring  "\n"
       (which can be translated into a newline character).

       There are several optional features:

       •   Unless dialog_vars.no_nl_expand is set,

       •   If  it has "\n" substrings, the function preserves extra spaces.  For instance, spaces
           following a newline (substring or character) are preserved to use as an indentation.

       •   The function changes embedded "\n" substrings to '\n' characters.

       •   If dialog_vars.no_nl_expand is not set, or if  there  are  no  "\n"  substrings,  this
           function strips all extra spaces to simplify justification.

       •   If  dialog_vars.cr_wrap  is  set,  the  function  preserves  '\n'  newline characters.
           Otherwise, each '\n' newline character is converted to a space.

       •   Unless dialog_vars.nocollapse is set, each tab character is converted to a space,  and
           sequences of blanks (space or tab) are reduced to a single space.

       char * src
            is the string to trim

   dlg_unregister_window
       Remove the bindings for a given window.

       WINDOW * win
            is the window from which to remove bindings

   dlg_update_gauge
       Update a gauge widget to show a different percentage value.

       void *objptr
            points to the gauge object to update.

       int percent
            is the new percentage value to display.

   dlg_yes_buttoncode
       Map the given button index for dlg_yes_labels into dialog's exit-code.

       int button
            is the button index

   dlg_yes_labels
       Return a list of buttons for Yes/No labels.

   end_dialog
       End use of dialog functions.

   init_dialog
       Do some initialization for dialog.

       FILE *input
            is the real tty input of dialog.  Usually it is the standard input, but if --input-fd
            option is used, it may be anything.

       FILE *output
            is where dialog will send its result.  Usually it  is  the  standard  error,  but  if
            --stdout or --output-fd is used, it may be anything.

SEE ALSO

       dialog (1).

AUTHOR

       Thomas E. Dickey

$Date: 2016/02/07 01:56:43 $                                                            DIALOG(3)