- tput, reset - initialize a terminal or query terminfo
- database
+ tput - initialize a terminal, exercise its capabilities, or query term-
+ info database
- 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 out-
- put, 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 out-
- put.
-
- 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 EXITCODES and DIAG-
- NOSTICS sections.) For a complete list of capabilities
- and the capname associated with each, see terminfo(5).
+ 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.
-
- -Ttype indicates the type of terminal. Normally this
- option is unnecessary, because the default is taken
- from the environment variable TERM. If -T is spec-
- ified, then the shell variables LINES and COLUMNS
- will also be ignored.
+ numeric tput writes cap-code's decimal value to the standard output
+ stream if defined (-1 if it is not) followed by a newline.
- -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).
+ string tput writes cap-code's value to the standard output stream if
+ defined, without a trailing newline.
- Again, tput uses a table and the presence of param-
- eters in its input to decide whether to use
- tparm(3x), and how to interpret the parameters.
+ 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.
- -V reports the version of ncurses which was used in
- this program, and exits.
+
+ 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".
-
- 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 ter-
- minfo(5) for a list). Although init and reset resemble
- capability names, tput uses several capabilities to per-
- form these special functions.
+ cap-code indicates a capability from the terminal database.
- capname
- indicates the capability from the terminal data-
- base.
+ 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.
- If the capability is a string that takes parame-
- ters, the arguments following the capability will
- be used as parameters for the string.
+ 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.
- 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 substitu-
- tion.
+ init initializes the terminal. If the terminal database is
+ present and an entry for the user's terminal type exists,
+ the following occur.
- init If the terminal database is present and an entry
- for the user's terminal exists (see -Ttype, above),
- the following will occur:
+ (1) tput retrieves the terminal's mode settings. It
+ successively tests the file descriptors corresponding
+ to
- (1) first, tput retrieves the current terminal
- mode settings for your terminal. It does this
- by successively testing
+ o the standard error stream,
- o the standard error,
+ o the standard output stream,
- o standard output,
+ o the standard input stream, and
- o standard input and
+ o/dev/tty
- o ultimately "/dev/tty"
+ to obtain terminal settings. Having retrieved them,
+ tput remembers which descriptor to use for further
+ updates.
- to obtain terminal settings. Having retrieved
- these settings, tput remembers which file
- descriptor to use when updating settings.
+ (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.
- (2) if the window size cannot be obtained from the
- operating system, but the terminal description
- (or environment, e.g., LINES and COLUMNS vari-
- ables specify this), update the operating sys-
- tem's notion of the window size.
+ (3) tput updates the terminal modes.
- (3) the terminal modes will be updated:
+ o Any delays specified in the entry (for example,
+ when a newline is sent) are set in the terminal
+ driver.
- o any delays (e.g., newline) specified in
- the entry will be set in the tty driver,
+ o Tab expansion is turned on or off per the
+ specification in the entry, and
- 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 (every 8
+ spaces) are set.
- o if tabs are not expanded, standard tabs
- will be set (every 8 spaces).
+ (4) If initialization capabilities, detailed in subsection
+ "Tabs and Initialization" of terminfo(5), are present,
+ tput writes them to the standard output stream.
- (4) if present, the terminal's initialization
- strings will be output as detailed in the ter-
- minfo(5) section on TabsandInitialization,
+ (5) tput flushes the standard output stream.
- (5) output is flushed.
+ If an entry lacks the information needed for an activity
+ above, that activity is silently skipped.
- If an entry does not contain the information needed
- for any of these activities, that activity will
- silently be skipped.
+ reset re-initializes the terminal. A reset differs from
+ initialization in two ways.
- reset This is similar to init, with two differences:
+ (1) tput sets the the terminal modes to a "sane" state,
- (1) before any other initialization, the terminal
- modes will be reset to a "sane" state:
+ o enabling cooked and echo modes,
- o set cooked and echo modes,
+ o disabling cbreak and raw modes,
- o turn off cbreak and raw modes,
+ o enabling newline translation, and
- o turn on newline translation and
+ o setting any unset special characters to their
+ default values.
- o reset 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).
- (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.
+ 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.
- Otherwise, reset acts identically to init.
+ 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.
- 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)].
+ 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 "tputinit" or "tputreset" 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).
- 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 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 "tputreset".
+
+ 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).
+
+
+
+ Besides the pseudo-capabilities (such as init), tput treats the lines
+ and colscap-codes specially: it may call setupterm(3x) to obtain the
+ terminal size.
+
+ o 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.
- If tput is invoked by a link named reset, this has the
- same effect as tputreset. The tset(1) utility also
- treats a link named reset specially.
+ o 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.
- Before ncurses 6.1, the two utilities were different from
- each other:
+ o Finally, it inspects the environment variables LINES and COLUMNS,
+ which may override the terminal size.
- otset utility reset the terminal modes and special
- characters (not done with tput).
+ 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).
- o On the other hand, tset's repertoire of terminal capa-
- bilities 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.
+
+ -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).
- With the changes made for ncurses 6.1, the reset feature
- of the two programs is (mostly) the same. A few differ-
- ences remain:
+ 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).
- o The tset program waits one second when resetting, in
- case it happens to be a hardware terminal.
+ -Ttype 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.
- 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).
+ -V reports the version of ncurses associated with tput, and exits
+ with a successful status.
- Note: although these programs write to different
- streams, redirecting their output to a file will cap-
- ture only part of their actions. The changes to the
- terminal modes are not affected by redirecting the
- output.
+ -x prevents "tputclear" from attempting to clear the scrollback
+ buffer.
- If tput is invoked by a link named init, this has the same
- effect as tputinit. Again, you are less likely to use
- that link because another program named init has a more
- well-established use.
+
+
+ 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.
+
+
+
+ Over time ncursestput has differed from that of System V in two
+ important respects, one now mostly historical.
+
+ o "tputcap-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.
+
+ o 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.
+
+ ncursestput 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.
+
+ o The cap-codedl means delete_line to termcap but parm_delete_line
+ to terminfo. termcap uses the code DL for parm_delete_line. term-
+ info uses the code dl1 for delete_line.
+
+ o The cap-codeed 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.
+
+ oncurses supports clear as it does any other standard cap-code. The
+ others (init and longname) do not correspond to terminal
+ capabilities.
+
+ o 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.
+
+ o 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 ncursestput, 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.
+
+ o X/Open Curses Issue 7 documents tput differently, with cap-code 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 capability database.
+
+ o 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).
+
+ o 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.
+
+ o 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.
+
+
+
+ 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.
+
+ o 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(3x) for
+ parameterized capabilities.
+
+ o 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.
+
+ o 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 ncursestput 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.
+
+ otset was more effective, resetting the terminal modes and special
+ characters.
+
+ o 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.
+
+ o The tset program waits one second when resetting, in case the
+ terminal happens to be a hardware device.
+
+ o The two programs write the terminal initialization strings to
+ different streams; that is, standard error for tset and standard
+ output for tput.
tputinit
- Initialize the terminal according to the type of ter-
- minal in the environmental variable TERM. This com-
- mand should be included in everyone's .profile after
- the environmental variable TERM has been exported, as
- illustrated on the profile(5) manual page.
+ 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 $HOME/.profile after exporting the TERM environment variable.
tput-T5620reset
- Reset an AT&T 5620 terminal, overriding the type of
- terminal in the environmental variable TERM.
+ Reset an AT&T 5620 terminal, overriding the terminal type in the
+ TERM environment variable.
- tputcup00
- Send the sequence to move the cursor to row 0, column
- 0 (the upper left corner of the screen, usually known
- as the "home" cursor position).
+ tputcnorm
+ Set cursor to normal visibility.
+
+ tputhome
+ Move the cursor to row 0, column 0: the upper left corner of the
+ screen, usually known as the "home" cursor position.
tputclear
- Echo the clear-screen sequence for the current termi-
- nal.
+ Clear the screen: write the clear_screen capability's value to
+ the standard output stream.
tputcols
- Print the number of columns for the current terminal.
+ Report the number of columns used by the current terminal type.
+
+ tput-Tadm3acols
+ Report the number of columns used by an ADM-3A terminal.
- tput-T450cols
- Print the number of columns for the 450 terminal.
+ strong=`tputsmso`normal=`tputrmso`
+ Set shell variables to capability values: strong and normal, to
+ begin and end, respectively, stand-out mode for the terminal.
+ One might use these to present a prompt.
- bold=`tputsmso`offbold=`tputrmso`
- Set the shell variables bold, to begin stand-out mode
- sequence, and offbold, to end standout mode sequence,
- for the current terminal. This might be followed by
- a prompt: echo"${bold}Pleasetypeinyourname:
- ${offbold}\c"
+ printf "${strong}Username:${normal} "
tputhc
- Set exit code to indicate if the current terminal is
- a hard copy terminal.
+ Indicate via exit status whether the terminal is a hard copy
+ device.
tputcup234
- Send the sequence to move the cursor to row 23, col-
- umn 4.
+ Move the cursor to row 23, column 4.
tputcup
- Send the terminfo string for cursor-movement, with no
- parameters substituted.
+ Report the value of the cursor_address (cup) capability (used
+ for cursor movement), with no parameters substituted.
tputlongname
- Print the long name from the terminfo database for
- the type of terminal specified in the environmental
- variable TERM.
-
- tput-S<<!
- >clear
- >cup1010
- >bold
- >!
-
- This example shows tput processing several capabili-
- ties 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.
-
-
-
- /usr/share/terminfo
- compiled terminal description database
+ Report the terminfo database's description of the terminal type
+ specified in the TERM environment variable.
- /usr/share/tabset/*
- tab settings for some terminals, in a format appro-
- priate to be output to the terminal (escape
- sequences that set margins and tabs); for more
- information, see the TabsandInitialization, sec-
- tion of terminfo(5)
-
-
-
- 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 cap-
- name is defined for this terminal type. To
- determine if capname is defined for this termi-
- nal 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.
-
- otherreset 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 DIAGNOS-
- TICS section.
-
-
-
- tput prints the following error messages and sets the cor-
- responding 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-T450lines and tput-T2621xmc)
- 1 no error message is printed, see the EXITCODES section.
- 2 usage error
- 3 unknown terminal type or no terminfo database
- 4 unknown terminfo capability capname
- >4 error occurred in -S
- ---------------------------------------------------------------------
+ tput-S
+ Process multiple capabilities. The -S option can be profitably
+ used with a shell "here document".
+ $ tput-S<<!
+ > clear
+ > cup1010
+ > bold
+ > !
-
- The tput command was begun by Bill Joy in 1980. The ini-
- tial 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 writ-
- ten 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 terminfocapabilities (clear,
- init, longname and reset). However (because he had only
- termcap available), it accepted termcapnames 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 the 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.
-
+ The foregoing clears the screen, moves the cursor to position
+ (10, 10) and turns on bold (extra bright) mode.
-
- This implementation of tput differs from AT&T tput in two
- important areas:
-
- otputcapname writes to the standard output. That need
- not be a regular terminal. However, the subcommands
- which manipulate terminal modes may not use the stan-
- dard 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, stan-
- dard 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 ulti-
- mately 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.
-
- This implementation (unlike others) can accept both term-
- cap 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-substitu-
- tion 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 corre-
- spond 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 op-
- erands.
-
- 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.
-
- 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 implemen-
- tation.
-
- 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.
+ tputclearcup1010bold
+ Perform the same actions as the foregoing "tput-S" example.