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NAME

       tput - initialize a terminal, exercise its capabilities, or query terminfo database

SYNOPSIS

       tput [-T terminal-type] {cap-code [parameter ...]} ...

       tput [-T terminal-type] [-x] clear

       tput [-T terminal-type] init

       tput [-T terminal-type] reset

       tput [-T terminal-type] longname

       tput -S

       tput -V

DESCRIPTION

       tput  uses  the  terminfo  library  and  database  to make terminal-specific capabilities and information
       available to the shell, to initialize or reset the terminal, or to report a description  of  the  current
       (or specified) terminal type.  Terminal capabilities are accessed by cap-code.

       terminfo(5) discusses terminal capabilities at length and presents a complete list of cap-codes.

       When retrieving capability values, the result depends upon the capability's type.

       Boolean  tput sets its exit status to 0 if the terminal possesses cap-code, and 1 if it does not.

       numeric  tput  writes cap-code's decimal value to the standard output stream if defined (-1 if it is not)
                followed by a newline.

       string   tput writes cap-code's value to the standard  output  stream  if  defined,  without  a  trailing
                newline.

       Before  using  a value returned on the standard output, the application should test tput's exit status to
       be sure it is 0; see section “EXIT STATUS” below.

   Operands
       Generally, an operand is a cap-code, a capability  code  from  the  terminal  database,  or  a  parameter
       thereto.   Three  others  are  specially  recognized  by tput: init, reset, and longname.  Although these
       resemble capability codes, they in fact receive special handling; we term them “pseudo-capabilities”.

       cap-code   indicates a capability from the terminal database.

                  If cap-code is of string type and takes parameters, tput interprets arguments  following  cap-
                  code as the parameters, up to the (fixed) quantity the capability requires.

                  Most parameters are numeric.  Only a few terminal capabilities require string parameters; tput
                  uses a table to decide which to pass  as  strings.   Normally  tput  uses  tparm(3NCURSES)  to
                  perform  the  substitution.   If  no  parameters are given for the capability, tput writes the
                  string without performing the substitution.

       init       initializes the terminal.  If the terminal database is present and an  entry  for  the  user's
                  terminal type exists, the following occur.

                  (1)  tput  retrieves the terminal's mode settings.  It successively tests the file descriptors
                       corresponding to

                       •   the standard error stream,

                       •   the standard output stream,

                       •   the standard input stream, and

                       •   /dev/tty

                       to obtain terminal settings.  Having retrieved them, tput remembers which  descriptor  to
                       use for further updates.

                  (2)  If  the  terminal  dimensions  cannot  be  obtained  from  the  operating system, but the
                       environment or terminal type database entry describes them, tput  updates  the  operating
                       system's notion of them.

                  (3)  tput updates the terminal modes.

                       •   Any  delays  specified  in the entry (for example, when a newline is sent) are set in
                           the terminal driver.

                       •   Tab expansion is turned on or off per the specification in the entry, and

                       •   if tabs are not expanded, standard tabs (every 8 spaces) are set.

                  (4)  If initialization capabilities, detailed  in  subsection  “Tabs  and  Initialization”  of
                       terminfo(5), are present, tput writes them to the standard output stream.

                  (5)  tput flushes the standard output stream.

                  If  an  entry  lacks  the  information needed for an activity above, that activity is silently
                  skipped.

       reset      re-initializes the terminal.  A reset differs from initialization in two ways.

                  (1)  tput sets the the terminal modes to a “sane” state,

                       •   enabling cooked and echo modes,

                       •   disabling cbreak and raw modes,

                       •   enabling newline translation, and

                       •   setting any unset special characters to their default values.

                  (2)  If any reset capabilities are defined for the terminal type,  tput  writes  them  to  the
                       output  stream.   Otherwise,  tput  uses  any defined initialization capabilities.  Reset
                       capabilities are detailed in subsection “Tabs and Initialization” of terminfo(5).

       longname   A terminfo entry begins with one or more names by which an application can refer to the entry,
                  before  the list of terminal capabilities.  The names are separated by “|” characters.  X/Open
                  Curses terms the last name the “long name”, and indicates that it may include blanks.

                  tic warns if the last name does not include blanks, to accommodate old terminfo  entries  that
                  treated  the  long  name  as  an  optional feature.  The long name is often referred to as the
                  description field.

                  If the terminal database is present and an entry for the user's  terminal  type  exists,  tput
                  reports  its  description  to  the  standard  output  stream, without a trailing newline.  See
                  terminfo(5).

       Note: Redirecting the output of “tput init” or “tput reset” to a file will capture  only  part  of  their
       actions.   Changes  to  the  terminal  modes  are  not affected by file descriptor redirection, since the
       terminal modes are altered via ioctl(2).

   Aliases
       If tput is invoked via link with any of the names clear, init, or reset, it operates as if run  with  the
       corresponding (pseudo-)capability operand.  For example, executing a link named reset that points to tput
       has the same effect as “tput reset”.

       This feature was introduced by ncurses 5.2 in 2000.  It is rarely used:

       clear  is a separate program, which is both smaller and more frequently executed.

       init   has the same name as another program in widespread use.

       reset  is provided by the tset(1) utility (also via a link named reset).

   Terminal Size
       Besides the pseudo-capabilities (such as init), tput treats the lines and cols  cap-codes  specially:  it
       may call setupterm(3NCURSES) to obtain the terminal size.

       •   First,  tput  attempts to obtain these capabilities from the terminal database.  This generally fails
           for terminal emulators, which lack a fixed window size and thus omit the capabilities.

       •   It then asks the operating system  for  the  terminal's  size,  which  generally  works,  unless  the
           connection is via a serial line that does not support “NAWS”: negotiations about window size.

       •   Finally,  it  inspects  the  environment variables LINES and COLUMNS, which may override the terminal
           size.

       If the -T option is given, tput ignores the environment variables by  calling  use_tioctl(TRUE),  relying
       upon the operating system (or, ultimately, the terminal database).

OPTIONS

       -S       retrieves  more  than one capability per invocation of tput.  The capabilities must be passed to
                tput from the standard input stream instead of from the command  line  (see  section  “EXAMPLES”
                below).  Only one cap-code is allowed per line.  The -S option changes the meanings of the 0 and
                1 exit statuses (see section “EXIT STATUS” below).

                Some capabilities use string parameters rather than numeric ones.  tput employs a built-in table
                and  the presence of parameters in its input to decide how to interpret them, and whether to use
                tparm(3NCURSES).

       -T type  indicates the terminal's type.  Normally this option is unnecessary, because a default is  taken
                from  the  TERM environment variable.  If specified, the environment variables LINES and COLUMNS
                are also ignored.

       -V       reports the version of ncurses associated with tput, and exits with a successful status.

       -x       prevents “tput clear” from attempting to clear the scrollback buffer.

EXIT STATUS

       Normally, one should interpret tput's exit statuses as follows.

       Status   Meaning When -S Not Specified
       ──────────────────────────────────────────────────────────────────────────────────────────────────────────
       0        Boolean or string capability present
       1        Boolean or numeric capability absent
       2        usage error or no terminal type specified
       3        unrecognized terminal type
       4        unrecognized capability code
       >4       system error (4 + errno)

       When the -S option is used, some statuses change meanings.

       Status   Meaning When -S Specified
       ──────────────────────────────────────────────────────────────────────────────────────────────────────────
       0        all operands interpreted
       1        unused
       4        some operands not interpreted

ENVIRONMENT

       tput reads one environment variable.

       TERM    denotes the terminal type.  Each terminal type is distinct, though  many  are  similar.   The  -T
               option overrides its value.

FILES

       /usr/share/tabset
              tab stop initialization database

       /etc/terminfo
              compiled terminal description database

PORTABILITY

       Over  time  ncurses  tput  has  differed  from that of System V in two important respects, one now mostly
       historical.

       •   “tput cap-code” writes to the standard output, which need not be a  terminal  device.   However,  the
           operands that manipulate terminal modes might not use the standard output.

           System V tput's init and reset operands use logic from 4.1cBSD tset, manipulating terminal modes.  It
           checks the same file descriptors (and /dev/tty) for association with a terminal device as ncurses now
           does,  and  if  none  are,  finally  assumes  a 1200 baud terminal.  When updating terminal modes, it
           ignores errors.

           Until ncurses 6.1 (see section “HISTORY” below), tput did not modify terminal modes.  It now  employs
           a scheme similar to System V, using functions shared with tset (and ultimately based on 4.4BSD tset).
           If it is not able to open a terminal (for instance, when run by cron(1)), tput exits  with  an  error
           status.

       •   System V  tput  assumes  that  the type of a cap-code operand is numeric if all the characters of its
           value are decimal numbers; if they are not, it treats cap-code as a string capability.

           Most implementations that provide support for cap-code operands use the tparm(3NCURSES)  function  to
           expand  its  parameters.  That function expects a mixture of numeric and string parameters, requiring
           tput to know which type to use.

           ncurses tput uses a table to determine the parameter types for the standard cap-code operands, and an
           internal function to analyze nonstandard cap-code operands.

           While  more  reliable  than System V's utility, a portability problem is introduced by this analysis.
           An OpenBSD developer adapted the internal library function from ncurses  to  port  NetBSD's  termcap-
           based  tput  to  terminfo,  and  modified  it to interpret multiple cap-codes (and parameters) on the
           command line.  Portable applications should not rely upon this feature; ncurses offers it to  support
           applications written specifically for OpenBSD.

       This  implementation,  unlike  others,  accepts both termcap and terminfo cap-codes if termcap support is
       compiled in.  In that case, however, the predefined termcap and  terminfo  codes  have  two  ambiguities;
       ncurses assumes the terminfo code.

       •   The cap-code dl means delete_line to termcap but parm_delete_line to terminfo.  termcap uses the code
           DL for parm_delete_line.  terminfo uses the code dl1 for delete_line.

       •   The cap-code ed means exit_delete_mode to termcap but clr_eos to terminfo.  termcap uses the code  cd
           for clr_eos.  terminfo uses the code rmdc for exit_delete_mode.

       The  longname  operand, -S option, and the parameter-substitution features used in the cup example below,
       were not supported in AT&T/USL curses before SVr4 (1989).  Later, 4.3BSD-Reno (1990)  added  support  for
       longname, and in 1994, NetBSD added support for the parameter-substitution features.

       IEEE Std 1003.1/The Open Group Base Specifications Issue 7 (POSIX.1-2008) documents only the clear, init,
       and reset operands.  A few observations of interest arise from that selection.

       •   ncurses supports clear as it does any other standard cap-code.  The others (init and longname) do not
           correspond to terminal capabilities.

       •   The  tput on SVr4-based systems such as Solaris, IRIX64, and HP-UX, as well as others such as AIX and
           Tru64, also support standard cap-code operands.

       •   A few platforms such as FreeBSD recognize termcap codes rather  than  terminfo  capability  codes  in
           their  respective  tput  commands.   Since  2010, NetBSD's tput uses terminfo codes.  Before that, it
           (like FreeBSD) recognized termcap codes.

           Beginning in 2021, FreeBSD uses ncurses tput, configured for both terminfo (tested first) and termcap
           (as a fallback).

       Because  (apparently) all certified Unix systems support the full set of capability codes, the reason for
       documenting only a few may not be apparent.

       •   X/Open Curses Issue 7 documents tput differently, with cap-code and the other features used  in  this
           implementation.

       •   That  is,  there  are  two  standards  for  tput:  POSIX  (a  subset)  and  X/Open  Curses  (the full
           implementation).  POSIX documents a subset to avoid the complication of including X/Open  Curses  and
           the terminal capability database.

       •   While  it is certainly possible to write a tput program without using curses, no system with a curses
           implementation provides a tput utility that does not also support standard cap-codes.

       X/Open Curses Issue 7 (2009) is the first version to document utilities.  However  that  part  of  X/Open
       Curses does not follow existing practice (that is, System V curses behavior).

       •   It  assigns  exit  status  4  to  “invalid  operand”,  which  may  have  the same meaning as “unknown
           capability”.  For instance, the source code for Solaris xcurses uses the term “invalid” in this case.

       •   It assigns exit status 255 to a numeric variable that is not  specified  in  the  terminfo  database.
           That  likely  is a documentation error, mistaking the “-1” written to the standard output to indicate
           an absent or cancelled numeric capability for an (unsigned) exit status.

       The various System V implementations (AIX, HP-UX, Solaris) use the same exit statuses as ncurses.

       NetBSD curses documents exit statuses that correspond to neither ncurses nor X/Open Curses.

HISTORY

       Bill Joy wrote a tput command during development of 4BSD in October  1980.   This  initial  version  only
       cleared the screen, and did not ship with official distributions.

       System V developed a different tput command.

       •   SVr2 (1984) provided a rudimentary tput that checked the parameter against each predefined capability
           and returned the corresponding  value.   This  version  of  tput  did  not  use  tparm(3NCURSES)  for
           parameterized capabilities.

       •   SVr3  (1987)  replaced  that  with a more extensive program whose support for init and reset operands
           (more than half the program) incorporated the reset feature of BSD tset written by Eric Allman.

       •   SVr4 (1989) added color initialization by using the orig_colors (oc) and orig_pair (op)  capabilities
           in its init logic.

       Keith Bostic refactored BSD tput for shipment in 4.3BSD-Tahoe (1988), then replaced it the next year with
       a new implementation based on System V tput.  Bostic's version similarly accepted some  parameters  named
       for  terminfo  (pseudo-)capabilities:  clear,  init,  longname,  and reset.  However, because he had only
       termcap available, it accepted termcap codes for other capabilities.  Also, Bostic's  BSD  tput  did  not
       modify the terminal modes as the earlier BSD tset had done.

       At  the same time, Bostic added a shell script named “clear” that used tput to clear the screen.  Both of
       these appeared in 4.4BSD, becoming the “modern” BSD implementation of tput.

       The origin of ncurses tput lies outside both System V and BSD, in Ross Ridge's mytinfo package, published
       on  comp.sources.unix  in  December  1992.   Ridge's  program made more sophisticated use of the terminal
       capabilities than the BSD program.  Eric Raymond used that tput program (and other parts of  mytinfo)  in
       ncurses  in  June  1995.   Incorporating  the  portions dealing with terminal capabilities almost without
       change, Raymond made improvements to the way command-line parameters were handled.

       Before ncurses 6.1 (2018), its tset and tput utilities differed.

       •   tset was more effective, resetting the terminal modes and special characters.

       •   On the other hand, tset's repertoire of terminal capabilities for resetting  the  terminal  was  more
           limited;  it  had  only equivalents of reset_1string (rs1), reset_2string (rs2), and reset_file (rf),
           and not the tab stop and margin update features of tput.

       The reset program is traditionally an alias for tset due to its  ability  to  reset  terminal  modes  and
       special characters.

       As of ncurses 6.1, the “reset” features of the two programs are (mostly) the same.  Two minor differences
       remain.

       •   The tset program waits one second when resetting, in case the  terminal  happens  to  be  a  hardware
           device.

       •   The  two  programs  write the terminal initialization strings to different streams; that is, standard
           error for tset and standard output for tput.

EXAMPLES

       tput init
              Initialize the terminal according to the type of terminal in the TERM  environment  variable.   If
              the  system  does not reliably initialize the terminal upon login, this command can be included in
              $HOME/.profile after exporting the TERM environment variable.

       tput -T5620 reset
              Reset an AT&T 5620 terminal, overriding the terminal type in the TERM environment variable.

       tput cnorm
              Set cursor to normal visibility.

       tput home
              Move the cursor to row 0, column 0: the upper left corner of the  screen,  usually  known  as  the
              “home” cursor position.

       tput clear
              Clear the screen: write the clear_screen capability's value to the standard output stream.

       tput cols
              Report the number of columns used by the current terminal type.

       tput -Tadm3a cols
              Report the number of columns used by an ADM-3A terminal.

       strong=`tput smso` normal=`tput rmso`
              Set  shell  variables  to  capability  values:  strong and normal, to begin and end, respectively,
              stand-out mode for the terminal.  One might use these to present a prompt.

                     printf "${strong}Username:${normal} "

       tput hc
              Indicate via exit status whether the terminal is a hard copy device.

       tput cup 23 4
              Move the cursor to row 23, column 4.

       tput cup
              Report the value of the cursor_address (cup)  capability  (used  for  cursor  movement),  with  no
              parameters substituted.

       tput longname
              Report  the terminfo database's description of the terminal type specified in the TERM environment
              variable.

       tput -S
              Process multiple capabilities.  The -S option can be profitably used with a shell “here document”.

              $ tput -S <<!
              > clear
              > cup 10 10
              > bold
              > !

              The foregoing clears the screen, moves the cursor to position (10, 10) and turns  on  bold  (extra
              bright) mode.

       tput clear cup 10 10 bold
              Perform the same actions as the foregoing “tput -S” example.

SEE ALSO

       clear(1), stty(1), tabs(1), tset(1), termcap(3NCURSES), terminfo(5)