Provided by: ncurses-bin_6.1+20181013-2ubuntu2_amd64 bug

NAME

       tput, reset - initialize a terminal or query terminfo database

SYNOPSIS

       tput [-Ttype] capname [parameters]
       tput [-Ttype] [-x] clear
       tput [-Ttype] init
       tput [-Ttype] reset
       tput [-Ttype] longname
       tput -S  <<
       tput -V

DESCRIPTION

       The  tput  utility  uses  the  terminfo  database to make the values of terminal-dependent
       capabilities and information available to the shell (see sh(1)), to  initialize  or  reset
       the  terminal, or return the long name of the requested terminal type.  The result depends
       upon the capability's type:

          string
               tput writes the string to the standard output.  No trailing newline is supplied.

          integer
               tput writes the decimal value to the standard output, with a trailing newline.

          boolean
               tput simply sets the exit code (0 for TRUE if the terminal has the  capability,  1
               for FALSE if it does not), and writes nothing to the standard output.

       Before using a value returned on the standard output, the application should test the exit
       code (e.g., $?, see sh(1)) to be sure it is  0.   (See  the  EXIT  CODES  and  DIAGNOSTICS
       sections.)   For a complete list of capabilities and the capname associated with each, see
       terminfo(5).

   Options
       -S     allows more than one capability per invocation of tput.  The capabilities  must  be
              passed  to  tput  from  the  standard  input  instead of from the command line (see
              example).  Only one capname is allowed per line.  The -S option changes the meaning
              of the 0 and 1 boolean and string exit codes (see the EXIT CODES section).

              Because  some capabilities may use string parameters rather than numbers, tput uses
              a table and the presence of parameters in  its  input  to  decide  whether  to  use
              tparm(3X), and how to interpret the parameters.

       -Ttype indicates  the  type of terminal.  Normally this option is unnecessary, because the
              default is taken from the environment variable TERM.  If -T is specified, then  the
              shell variables LINES and COLUMNS will also be ignored.

       -V     reports the version of ncurses which was used in this program, and exits.

       -x     do  not  attempt  to clear the terminal's scrollback buffer using the extended “E3”
              capability.

   Commands
       A few commands (init, reset and longname) are  special;  they  are  defined  by  the  tput
       program.   The  others  are  the  names  of  capabilities  from the terminal database (see
       terminfo(5) for a list).  Although init and reset resemble  capability  names,  tput  uses
       several capabilities to perform these special functions.

       capname
              indicates the capability from the terminal database.

              If  the  capability  is a string that takes parameters, the arguments following the
              capability will be used as parameters for the string.

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

       init   If  the  terminal  database  is present and an entry for the user's terminal exists
              (see -Ttype, above), the following will occur:

              (1)  first, tput retrieves the current terminal mode settings  for  your  terminal.
                   It does this by successively testing

                   ·   the standard error,

                   ·   standard output,

                   ·   standard input and

                   ·   ultimately “/dev/tty”

                   to  obtain terminal settings.  Having retrieved these settings, tput remembers
                   which file descriptor to use when updating settings.

              (2)  if the window size cannot be obtained  from  the  operating  system,  but  the
                   terminal  description  (or  environment,  e.g.,  LINES  and  COLUMNS variables
                   specify this), update the operating system's notion of the window size.

              (3)  the terminal modes will be updated:

                   ·   any delays (e.g., newline) specified in the entry will be set in  the  tty
                       driver,

                   ·   tabs  expansion will be turned on or off according to the specification in
                       the entry, and

                   ·   if tabs are not expanded, standard tabs will be set (every 8 spaces).

              (4)  if present, the terminal's initialization strings will be output  as  detailed
                   in the terminfo(5) section on Tabs and Initialization,

              (5)  output is flushed.

              If  an  entry  does not contain the information needed for any of these activities,
              that activity will silently be skipped.

       reset  This is similar to init, with two differences:

              (1)  before any other initialization, the terminal modes will be reset to a  “sane”
                   state:

                   ·   set cooked and echo modes,

                   ·   turn off cbreak and raw modes,

                   ·   turn on newline translation and

                   ·   reset any unset special characters to their default values

              (2)  Instead  of  putting  out initialization strings, the terminal's reset strings
                   will be output if present (rs1, rs2, rs3, rf).  If the reset strings  are  not
                   present,  but  initialization  strings are, the initialization strings will be
                   output.

              Otherwise, reset acts identically to init.

       longname
              If the terminal database is present and an entry for  the  user's  terminal  exists
              (see  -Ttype  above), then the long name of the terminal will be put out.  The long
              name is the last name in the first  line  of  the  terminal's  description  in  the
              terminfo database [see term(5)].

   Aliases
       tput  handles  the clear, init and reset commands specially: it allows for the possibility
       that it is invoked by a link with those names.

       If tput is invoked by a link named reset, this has the same effect  as  tput  reset.   The
       tset(1) utility also treats a link named reset specially.

       Before ncurses 6.1, the two utilities were different from each other:

       ·   tset utility reset the terminal modes and special characters (not done with tput).

       ·   On  the  other  hand,  tset's  repertoire  of  terminal capabilities for resetting the
           terminal was more limited, i.e., only reset_1string, reset_2string and  reset_file  in
           contrast to the tab-stops and margins which are set by this utility.

       ·   The  reset  program  is  usually  an  alias  for tset, because of this difference with
           resetting terminal modes and special characters.

       With the changes made for ncurses 6.1, the reset feature of the two programs  is  (mostly)
       the same.  A few differences remain:

       ·   The  tset program waits one second when resetting, in case it happens to be a hardware
           terminal.

       ·   The two programs write the terminal initialization strings to different streams (i.e.,
           the standard error for tset and the standard output for tput).

           Note:  although these programs write to different streams, redirecting their output to
           a file will capture only part of their actions.  The changes to the terminal modes are
           not affected by redirecting the output.

       If  tput  is  invoked by a link named init, this has the same effect as tput init.  Again,
       you are less likely to use that link because another program named init has a  more  well-
       established use.

   Terminal Size
       Besides  the  special  commands  (e.g.,  clear), tput treats certain terminfo capabilities
       specially: lines and columns.  tput calls setupterm(3X) to obtain the terminal size:

       ·   first, it gets the size from the terminal database (which generally  is  not  provided
           for terminal emulators which do not have a fixed window size)

       ·   then  it  asks  the  operating  system for the terminal's size (which generally works,
           unless connecting via a serial line which 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 finally, the terminal database).

EXAMPLES

       tput init
            Initialize  the  terminal  according  to  the  type  of terminal in the environmental
            variable TERM.  This command should be included  in  everyone's  .profile  after  the
            environmental  variable  TERM  has  been  exported,  as illustrated on the profile(5)
            manual page.

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

       tput cup 0 0
            Send the sequence to move the cursor to row 0, column 0 (the upper left corner of the
            screen, usually known as the “home” cursor position).

       tput clear
            Echo the clear-screen sequence for the current terminal.

       tput cols
            Print the number of columns for the current terminal.

       tput -T450 cols
            Print the number of columns for the 450 terminal.

       bold=`tput smso` offbold=`tput rmso`
            Set the shell variables bold, to begin stand-out mode sequence, and offbold,  to  end
            standout  mode  sequence,  for  the  current  terminal.   This might be followed by a
            prompt: echo "${bold}Please type in your name: ${offbold}\c"

       tput hc
            Set exit code to indicate if the current terminal is a hard copy terminal.

       tput cup 23 4
            Send the sequence to move the cursor to row 23, column 4.

       tput cup
            Send the terminfo string for cursor-movement, with no parameters substituted.

       tput longname
            Print the long name from the terminfo database for the type of terminal specified  in
            the environmental variable TERM.

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

            This example shows tput processing several capabilities in one invocation.  It clears
            the screen, moves the cursor to position 10, 10 and  turns  on  bold  (extra  bright)
            mode.  The list is terminated by an exclamation mark (!) on a line by itself.

FILES

       /etc/terminfo
              compiled terminal description database

       /usr/share/tabset/*
              tab  settings  for  some  terminals,  in  a  format appropriate to be output to the
              terminal (escape sequences that set margins and tabs); for  more  information,  see
              the Tabs and Initialization, section of terminfo(5)

EXIT CODES

       If  the  -S  option  is used, tput checks for errors from each line, and if any errors are
       found, will set the exit code to 4 plus the number of lines with errors.  If no errors are
       found, the exit code is 0.  No indication of which line failed can be given so exit code 1
       will never appear.  Exit codes 2, 3, and 4 retain their usual interpretation.  If  the  -S
       option is not used, the exit code depends on the type of capname:

          boolean
                 a value of 0 is set for TRUE and 1 for FALSE.

          string a  value of 0 is set if the capname is defined for this terminal type (the value
                 of capname is returned on standard output); a value of 1 is set  if  capname  is
                 not defined for this terminal type (nothing is written to standard output).

          integer
                 a  value of 0 is always set, whether or not capname is defined for this terminal
                 type.  To determine if capname is defined for this terminal type, the user  must
                 test  the value written to standard output.  A value of -1 means that capname is
                 not defined for this terminal type.

          other  reset or init may fail to find their respective files.  In that case,  the  exit
                 code is set to 4 + errno.

       Any other exit code indicates an error; see the DIAGNOSTICS section.

DIAGNOSTICS

       tput prints the following error messages and sets the corresponding exit codes.

       exit code   error message
       ─────────────────────────────────────────────────────────────────────
       0           (capname  is a numeric variable that is not specified in
                   the terminfo(5) database for this  terminal  type,  e.g.
                   tput -T450 lines and tput -T2621 xmc)
       1           no error message is printed, see the EXIT CODES section.
       2           usage error
       3           unknown terminal type or no terminfo database
       4           unknown terminfo capability capname
       >4          error occurred in -S
       ─────────────────────────────────────────────────────────────────────

HISTORY

       The  tput  command  was  begun  by Bill Joy in 1980.  The initial version only cleared the
       screen.

       AT&T System V provided a different tput command, whose init and reset   subcommands  (more
       than  half  the  program)  were incorporated from the reset feature of BSD tset written by
       Eric Allman.

       Keith Bostic replaced the BSD tput command in 1989 with a new implementation based on  the
       AT&T  System  V  program  tput.   Like  the  AT&T  program, Bostic's version accepted some
       parameters named for terminfo capabilities (clear, init,  longname  and  reset).   However
       (because he had only termcap available), it accepted termcap names for other capabilities.
       Also, Bostic's BSD tput did not modify the terminal I/O modes as the earlier BSD tset  had
       done.

       At  the same time, Bostic added a shell script named “clear”, which used tput to clear the
       screen.

       Both of these appeared in 4.4BSD, becoming the “modern” BSD implementation of tput.

       This implementation of tput began from a different source than AT&T or BSD:  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.  Using the
       portions  dealing  with  terminal  capabilities  almost  without  change,   Raymond   made
       improvements to the way the command-line parameters were handled.

PORTABILITY

       This implementation of tput differs from AT&T tput in two important areas:

       ·   tput  capname  writes  to  the  standard output.  That need not be a regular terminal.
           However, the subcommands which manipulate terminal modes  may  not  use  the  standard
           output.

           The  AT&T  implementation's  init  and  reset commands use the BSD (4.1c) tset source,
           which manipulates terminal modes.  It successively  tries  standard  output,  standard
           error,  standard  input  before  falling back to “/dev/tty” and finally just assumes a
           1200Bd terminal.  When updating terminal modes, it ignores errors.

           Until changes made after ncurses 6.0, tput did not modify terminal  modes.   tput  now
           uses  a  similar scheme, using functions shared with tset (and ultimately based on the
           4.4BSD tset).  If it is not able to open a terminal, e.g., when running in cron,  tput
           will return an error.

       ·   AT&T  tput guesses the type of its capname operands by seeing if all of the characters
           are numeric, or not.

           Most implementations which provide support for capname operands use the tparm function
           to  expand  parameters  in  it.  That function expects a mixture of numeric and string
           parameters, requiring tput to know which type to use.

           This implementation uses a table to determine the parameter  types  for  the  standard
           capname  operands,  and  an  internal  library function to analyze nonstandard capname
           operands.

       This implementation (unlike others) can accept both termcap and  terminfo  names  for  the
       capname  feature,  if termcap support is compiled in.  However, the predefined termcap and
       terminfo names have two ambiguities in this case (and the terminfo name is assumed):

       ·   The termcap name dl corresponds to the terminfo name dl1 (delete one line).
           The terminfo name dl corresponds to the termcap name DL  (delete  a  given  number  of
           lines).

       ·   The termcap name ed corresponds to the terminfo name rmdc (end delete mode).
           The terminfo name ed corresponds to the termcap name cd (clear to end of screen).

       The  longname  and  -S  options,  and  the parameter-substitution features used in the cup
       example, were not supported in BSD curses before 4.3reno  (1989)  or  in  AT&T/USL  curses
       before SVr4 (1988).

       IEEE  Std 1003.1/The Open Group  Base Specifications Issue 7 (POSIX.1-2008) documents only
       the operands for clear, init and reset.  There are a few interesting observations to  make
       regarding that:

       ·   In  this  implementation,  clear is part of the capname support.  The others (init and
           longname) do not correspond to terminal capabilities.

       ·   Other implementations of tput on SVr4-based systems such as Solaris, IRIX64  and  HPUX
           as well as others such as AIX and Tru64 provide support for capname operands.

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

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

       ·   X/Open Curses Issue 7 documents tput differently, with capname 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 capabilities database.

       ·   While  it  is certainly possible to write a tput program without using curses, none of
           the systems which have a curses implementation provide a tput utility which  does  not
           provide the capname feature.

       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 (i.e., Unix features documented in
       SVID 3):

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

       ·   It  assigns  exit code 255 to a numeric variable that is not specified in the terminfo
           database.  That likely is a documentation error,  confusing  the  -1  written  to  the
           standard  output  for  an  absent or cancelled numeric value versus an (unsigned) exit
           code.

       The various Unix systems (AIX, HPUX, Solaris) use the same exit-codes as ncurses.

       NetBSD curses documents different exit codes which do not correspond to either ncurses  or
       X/Open.

SEE ALSO

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

       This describes ncurses version 6.1 (patch 20181013).

                                                                                          tput(1)