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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)