ncurses 6.0 - patch 20161029

[ncurses.git] / man / tput.1

diff --git a/man/tput.1 b/man/tput.1
index 46f19668a59a52eee4a2e62e498dae6ca4b8e6d7..6aafe816534377410ea71711855d4565c9fdd42f 100644 (file)
--- a/man/tput.1
+++ b/man/tput.1
@@ -27,7 +27,7 @@
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"

-.\" $Id: tput.1,v 1.42 2016/07/30 21:01:09 tom Exp $
+.\" $Id: tput.1,v 1.46 2016/10/22 19:57:25 tom Exp $

 .TH @TPUT@ 1 ""
 .ds d @TERMINFO@
 .ds n 1
 .TH @TPUT@ 1 ""
 .ds d @TERMINFO@
 .ds n 1


@@ -168,21 +168,25 @@ 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
 \fBterminfo\fR database [see \fBterm\fR(5)].
 .SS Aliases
 name in the first line of the terminal's description in the
 \fBterminfo\fR database [see \fBterm\fR(5)].
 .SS Aliases

-\fB@TPUT@\fR handles the \fBinit\fP and \fBreset\fP commands specially:
+\fB@TPUT@\fR handles the \fBclear\fP, \fBinit\fP and \fBreset\fP
+commands specially:

 it allows for the possibility that it is invoked by a link with those names.
 .PP
 If \fB@TPUT@\fR is invoked by a link named \fBreset\fR, this has the
 same effect as \fB@TPUT@ reset\fR.
 it allows for the possibility that it is invoked by a link with those names.
 .PP
 If \fB@TPUT@\fR is invoked by a link named \fBreset\fR, this has the
 same effect as \fB@TPUT@ reset\fR.

-The \fB@TSET@\fR(\*n) utility also treats a link named \fBreset\fP specially:
+The \fB@TSET@\fR(\*n) utility also treats a link named \fBreset\fP specially.
+.PP
+Before ncurses 6.1, the two utilities were different from each other:

 .bP
 .bP

-That utility resets the terminal modes and special characters (not done here).
+\fB@TSET@\fP utility reset the terminal modes and special characters
+(not done with \fB@TPUT@\fP).

 .bP
 .bP

-On the other hand, @TSET@'s repertoire of terminal capabilities for
-resetting the terminal is more limited, i.e., only \fBreset_1string\fP, \fBreset_2string\fP and \fBreset_file\fP
+On the other hand, \fB@TSET@\fP's repertoire of terminal capabilities for
+resetting the terminal was more limited, i.e., only \fBreset_1string\fP, \fBreset_2string\fP and \fBreset_file\fP

 in contrast to the tab-stops and margins which are set by this utility.
 .bP
 in contrast to the tab-stops and margins which are set by this utility.
 .bP

-The \fBreset\fP program is usually an alias for @TSET@,
-due to the resetting of terminal modes and special characters.
+The \fBreset\fP program is usually an alias for \fB@TSET@\fP,
+because of this difference with resetting terminal modes and special characters.

 .PP
 If \fB@TPUT@\fR is invoked by a link named \fBinit\fR, this has the
 same effect as \fB@TPUT@ init\fR.
 .PP
 If \fB@TPUT@\fR is invoked by a link named \fBinit\fR, this has the
 same effect as \fB@TPUT@ init\fR.


@@ -328,13 +332,23 @@ T}
 The \fBtput\fP command was begun by Bill Joy in 1980.
 The initial version only cleared the screen.
 .PP
 The \fBtput\fP command was begun by Bill Joy in 1980.
 The initial version only cleared the screen.
 .PP

-Keith Bostic replaced this in 1989 with a new implementation
-based on the AT&T SystemV program \fBtput\fP.
+AT&T System V provided a different \fBtput\fP command,
+whose \fBinit\fP and \fBreset\fP  subcommands
+(more than half the program) were incorporated from
+the \fBreset\fP feature of BSD \fBtset\fP written by Eric Allman.
+Later the corresponding source code for \fIreset\fP
+was removed from the BSD \fBtset\fP
+(in June 1993, released in 4.4BSD-Lite a year later).
+.PP
+Keith Bostic replaced the BSD \fBtput\fP command in 1989 with a new implementation
+based on the AT&T System V program \fBtput\fP.

 Like the AT&T program, Bostic's version
 accepted some parameters named for \fIterminfo capabilities\fP
 (\fBclear\fP, \fBinit\fP, \fBlongname\fP and \fBreset\fP).
 However (because he had only termcap available),
 it accepted \fItermcap names\fP for other capabilities.
 Like the AT&T program, Bostic's version
 accepted some parameters named for \fIterminfo capabilities\fP
 (\fBclear\fP, \fBinit\fP, \fBlongname\fP and \fBreset\fP).
 However (because he had only termcap available),
 it accepted \fItermcap names\fP for other capabilities.

+Also, Bostic's BSD \fBtput\fP did not modify the terminal I/O modes
+as the earlier BSD \fBtset\fP had done.

 .PP
 At the same time, Bostic added a shell script named \*(lqclear\*(rq,
 which used \fBtput\fP to clear the screen.
 .PP
 At the same time, Bostic added a shell script named \*(lqclear\*(rq,
 which used \fBtput\fP to clear the screen.


@@ -346,15 +360,24 @@ becoming the \*(lqmodern\*(rq BSD implementation of \fBtput\fP.
 This implementation of \fBtput\fP differs from AT&T \fBtput\fP in
 two important areas:
 .bP
 This implementation of \fBtput\fP differs from AT&T \fBtput\fP in
 two important areas:
 .bP

-@TPUT@ writes to the standard output.
+\fB@TPUT@\fP \fIcapname\fP writes to the standard output.

 That need not be a regular terminal.
 That need not be a regular terminal.

+However, the subcommands which manipulate terminal modes
+may not use the standard output.

 .IP
 The AT&T implementation's \fBinit\fP and \fBreset\fP commands
 .IP
 The AT&T implementation's \fBinit\fP and \fBreset\fP commands

-use the \fBtset\fP source, which manipulates terminal modes.
+use the BSD (4.1c) \fBtset\fP source, which manipulates terminal modes.

 It successively tries standard output, standard error, standard input
 before falling back to \*(lq/dev/tty\*(rq and finally just assumes
 a 1200Bd terminal.
 When updating terminal modes, it ignores errors.
 It successively tries standard output, standard error, standard input
 before falling back to \*(lq/dev/tty\*(rq and finally just assumes
 a 1200Bd terminal.
 When updating terminal modes, it ignores errors.

+.IP
+Until changes made after ncurses 6.0, \fB@TPUT@\fP did not modify terminal modes.
+\fB@TPUT@\fP now uses a similar scheme,
+using functions shared with \fB@TSET@\fP
+(and ultimately based on the 4.4BSD \fBtset\fP).
+If it is not able to open a terminal, e.g., when running in \fBcron\fP,
+\fB@TPUT@\fP will return an error.

 .bP
 AT&T \fBtput\fP guesses the type of its \fIcapname\fP operands by seeing if
 all of the characters are numeric, or not.
 .bP
 AT&T \fBtput\fP guesses the type of its \fIcapname\fP operands by seeing if
 all of the characters are numeric, or not.