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NAME | SYNOPSIS | DESCRIPTION | OPTIONS | EXIT STATUS | ENVIRONMENT | FILES | PORTABILITY | HISTORY | EXAMPLES | SEE ALSO | COLOPHON |
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tput(1) User commands tput(1)
tput - initialize a terminal, exercise its capabilities, or query
terminfo database
tput [-v] [-T terminal-type] {cap-code [parameter ...]} ...
tput [-v] [-T terminal-type] [-x] clear
tput [-v] [-T terminal-type] init
tput [-v] [-T terminal-type] reset
tput [-v] [-T terminal-type] longname
tput [-v] -S
tput [-v] -V
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 standardized cap-codes. user_caps(5) presents
other widely used but non-standard capabilities.
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(3X) 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.
• 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 terminal modes to a “sane” state,
• enabling canonical (“cooked”) and echo modes,
• disabling cbreak and raw modes,
• enabling newline translation, and
• setting any special input 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(3X) 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).
-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(3X).
-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 causes tput to operate verbosely, reporting warnings.
-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.
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
tput reads up to three environment variables if the -T option is
not specified.
COLUMNS
specifies the width of the screen in characters.
LINES specifies the height of the screen in characters.
TERM denotes the terminal type. Each terminal type is distinct,
though many are similar.
datadir/tabset
tab stop initialization database
terminfo
compiled terminal description database
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(3X) 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.
ncurses's implementation of tput, unlike others, accepts both
termcap and terminfo cap-codes if termcap support is compiled in.
In that case, however, 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 canceled 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.
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 capability name and returned the
corresponding value. This version of tput did not use
tparm(3X) 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-Reno
(1990), making it follow the interface of System V tput by
accepting 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. These became 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's modes and
special input 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 the terminal's modes and special input
characters.
As of ncurses 6.1, the “reset” features of the two programs are
(mostly) the same. Two minor differences remain.
• When issuing a reset, the tset program checks whether the
device appears to be a pseudoterminal (as might be used by a
terminal emulator program), and, if it does not, waits one
second in case it is communicating with a hardware terminal.
• The two programs write the terminal initialization strings to
different streams; that is, standard error for tset and
standard output for tput.
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 $HOME/.profile after exporting the TERM
environment variable.
tput -T5620 reset
Reset an AT&T 5620 terminal, overriding the terminal type
in the TERM environment variable.
tput cnorm
Set cursor to normal visibility.
tput home
Move the cursor to line 0, column 0: the upper left corner
of the screen, usually known as the “home” cursor position.
tput clear
Clear the screen: write the clear_screen capability's value
to the standard output stream.
tput cols
Report the number of columns used by the current terminal
type.
tput -Tadm3a cols
Report the number of columns used by an ADM-3A terminal.
strong=`tput smso` normal=`tput rmso`
Set shell variables to capability values: strong and
normal, to begin and end, respectively, stand-out mode for
the terminal. One might use these to present a prompt.
printf "${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 line 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.
clear(1), stty(1), tabs(1), tset(1), curs_termcap(3X),
terminfo(5), user_caps(5)
This page is part of the ncurses (new curses) project.
Information about the project can be found at
⟨https://invisible-island.net/ncurses/ncurses.html⟩. If you have a
bug report for this manual page, send it to bug-ncurses@gnu.org.
This page was obtained from the tarball ncurses-6.6.tar.gz fetched
from ⟨https://ftp.gnu.org/gnu/ncurses/⟩ on 2026-01-16. If you
discover any rendering problems in this HTML version of the page,
or you believe there is a better or more up-to-date source for the
page, or you have corrections or improvements to the information
in this COLOPHON (which is not part of the original manual page),
send a mail to man-pages@man7.org
ncurses @NCURSES_MAJOR@.@NCU... 2025-11-11 tput(1)
Pages that refer to this page: clear(1), setterm(1), curs_terminfo(3x), termios(3), console_codes(4)
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HTML rendering created 2026-01-16 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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