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tput 1

tput(1)                     General Commands Manual                    tput(1)




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

                   o   the standard error,

                   o   standard output,

                   o   standard input and

                   o   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:

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

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

                   o   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:

                   o   set cooked and echo modes,

                   o   turn off cbreak and raw modes,

                   o   turn on newline translation and

                   o   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:

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

       o   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.

       o   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:

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

       o   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   cols.    tput   calls
       setupterm(3x) to obtain the terminal size:

       o   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)

       o   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).

       o   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

       /usr/share/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 -Thp2621 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:

       o   SVr2 provided  a  rudimentary  tput  which  checked  the  parameter
           against  each  predefined capability and returned the corresponding
           value.  This  version  of  tput  did  not  use  tparm(3x)  for  the
           capabilities which are parameterized.

       o   SVr3 replaced that, a year later, by a more extensive program whose
           init and reset  subcommands  (more  than  half  the  program)  were
           incorporated  from  the  reset  feature of BSD tset written by Eric
           Allman.

       o   SVr4  added  color  initialization  using   the   orig_colors   and
           orig_pairs capabilities in the init subcommand.

       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:

       o   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.

       o   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.

           Besides  providing  more  reliable operation than AT&T'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.   That  had  been
           modified  to  interpret  multiple  commands  on  a  line.  Portable
           applications should not rely upon this feature; ncurses provides it
           to support applications written specifically for OpenBSD.

       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):

       o   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).

       o   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:

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

       o   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.

       o   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.

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

       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.

       o   X/Open Curses Issue 7 documents tput differently, with capname  and
           the other features used in this implementation.

       o   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.

       o   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):

       o   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.

       o   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), curs_termcap(3x), terminfo(5).

       This describes ncurses version 6.3 (patch 20211021).



                                                                       tput(1)