X-Git-Url: https://ncurses.scripts.mit.edu/?a=blobdiff_plain;f=man%2Ftabs.1;h=84c6b22e880c2d0b24f8d249d441bed34772619c;hb=HEAD;hp=01ed44e4ad62aedf7db219625b72fef0e3545c22;hpb=159cd0555e0efc14be66c9c3a1548f58908b6a1d;p=ncurses.git

diff --git a/man/tabs.1 b/man/tabs.1
index 01ed44e4..30df4dd6 100644
--- a/man/tabs.1
+++ b/man/tabs.1
@@ -1,5 +1,5 @@
 .\"***************************************************************************
-.\" Copyright 2018-2021,2023 Thomas E. Dickey                                *
+.\" Copyright 2018-2023,2024 Thomas E. Dickey                                *
 .\" Copyright 2008-2016,2017 Free Software Foundation, Inc.                  *
 .\"                                                                          *
 .\" Permission is hereby granted, free of charge, to any person obtaining a  *
@@ -27,8 +27,8 @@
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"
-.\" $Id: tabs.1,v 1.52 2023/12/23 16:08:25 tom Exp $
-.TH @TABS@ 1 2023-12-23 "ncurses 6.4" "User commands"
+.\" $Id: tabs.1,v 1.65 2024/09/21 18:04:07 tom Exp $
+.TH @TABS@ 1 2024-09-21 "ncurses @NCURSES_MAJOR@.@NCURSES_MINOR@" "User commands"
 .ie \n(.g \{\
 .ds `` \(lq
 .ds '' \(rq
@@ -78,7 +78,7 @@ you should either reset tab-stops to the standard interval
 .PP
 .RS 4
 .EX
-tabs \-8
+@TABS@ \-8
 .EE
 .RE
 .PP
@@ -128,8 +128,8 @@ They are separated by a comma or a blank, for example,
 .PP
 .RS 4
 .EX
-tabs 1,6,11,16,21
-tabs 1 6 11 16 21
+@TABS@ 1,6,11,16,21
+@TABS@ 1 6 11 16 21
 .EE
 .RE
 .PP
@@ -139,7 +139,7 @@ e.g.,
 .PP
 .RS 4
 .EX
-tabs 1,+5,+5,+5,+5
+@TABS@ 1,+5,+5,+5,+5
 .EE
 .RE
 .PP
@@ -192,53 +192,77 @@ UNIVAC 1100 Assembler
 .br
 1,12,20,44
 .SS Margins
-A few terminals provide the capability for changing their left/right margins.
-The @TABS@ program has an option to use this feature:
+A few terminals expose a means of changing their left and right margins.
+\fB@TABS@\fP supports this feature with an option.
 .TP 5
 .BI +m \ margin
 The effect depends on whether the terminal has the margin capabilities:
 .RS
 .bP
 If the terminal provides the capability for setting the left margin,
-@TABS@ uses this, and adjusts the available width for tab-stops.
+\fB@TABS@\fP uses this,
+and adjusts the available tab stop widths.
 .bP
 If the terminal does not provide the margin capabilities,
-@TABS@ imitates the effect, putting the tab stops at the appropriate
-place on each line.
-The terminal's left-margin is not modified.
+\fB@TABS@\fP imitates their effect,
+putting tab stops at appropriate places on each line.
+The terminal's left margin is not modified.
 .RE
 .IP
-If the \fImargin\fP parameter is omitted, the default is 10.
-Use \fB+m0\fP to reset the left margin,
-i.e., to the left edge of the terminal's display.
-Before setting a left-margin,
-@TABS@ resets the margin to reduce problems which might arise
-on moving the cursor before the current left-margin.
+If the
+.I margin
+parameter is omitted,
+the default is 10.
+Use
+.B +m0
+to reset the left margin,
+that is,
+to make it the left edge of the terminal's display.
+Before setting a left margin,
+\fB@TABS@\fP resets the margin to reduce problems that might arise
+from moving the cursor to the left of the current left margin.
 .PP
-When setting or resetting the left-margin,
-@TABS@ may reset the right-margin.
+When setting or resetting the left margin,
+\fB@TABS@\fP may also reset the right margin.
 .SH FILES
 .TP
 .I @DATADIR@/tabset
 tab stop initialization database
 .SH PORTABILITY
-\fIIEEE Std 1003.1/The Open Group Base Specifications Issue 7\fP (POSIX.1-2008)
-describes a \fBtabs\fP utility.
-However
+IEEE Std 1003.1/The Open Group Base Specifications Issue\ 7
+(POSIX.1-2008)
+describes a
+.I tabs
+utility.
+However,
 .bP
-This standard describes a \fB+m\fP option, to set a terminal's left-margin.
+this standard describes a
+.B +m
+option to set a terminal's left margin.
 Very few of the entries in the terminal database provide the
-\fBsmgl\fP (\fBset_left_margin\fP) or
-\fBsmglp\fP (\fBset_left_margin_parm\fP)
-capability needed to support the feature.
+.B \%set_left_margin
+.RB ( smgl )
+or
+.B \%set_left_margin_parm
+.RB \%( smglp )
+capabilities needed to support the feature.
 .bP
-There is no counterpart in X/Open Curses Issue 7 for this utility,
-unlike \fB@TPUT@\fP(1).
+Unlike
+.IR tput ,
+.I tabs
+has no specification in X/Open Curses Issue\ 7.
 .PP
-The \fB\-d\fP (debug) and \fB\-n\fP (no-op) options are extensions not provided
-by other implementations.
+The
+.B \-d
+(debug) and
+.B \-n
+(no-op) options are
+.I \%ncurses
+extensions not provided by other implementations.
 .SH HISTORY
-A \fBtabs\fP utility appeared in PWB/Unix 1.0 (1977).
+A
+.I tabs
+utility appeared in PWB/Unix 1.0 (1977).
 .\" https://minnie.tuhs.org/cgi-bin/utree.pl?file=PWB1/sys/source/s2/\
 .\"   tabs.c
 A reduced version shipped in Seventh Edition Unix
@@ -248,14 +272,16 @@ and in 3BSD
 .\" https://minnie.tuhs.org/cgi-bin/utree.pl?file=3BSD/usr/src/cmd/\
 .\"   tabs.c
 (later the same year);
-it supported a \*(``\-n\*('' option to set the first tab stop at the
+it supported an option \*(``\-n\*('' to set the first tab stop at the
 left margin.
-That option is not documented by POSIX.
+That option is not specified by POSIX.
 .PP
-The PWB/Unix \fBtabs\fP utility returned in System III (1980),
-and used built-in tables rather than the terminal database,
+The PWB/Unix
+.I tabs
+utility returned in System III (1980),
+and used built-in tables
 to support a half-dozen hardcopy terminal (printer) types.
-It also had built-in logic to support setting the left margin,
+It also had logic to support setting the left margin,
 as well as a feature for copying the tab settings from a file.
 .PP
 Versions of the program in later releases of AT&T Unix,
@@ -263,50 +289,70 @@ such as SVr4,
 .\" https://minnie.tuhs.org/cgi-bin/utree.pl?file=SysVR4/cmd/tabs/tabs.c
 added support for the terminal database,
 but retained the tables to support the printers.
-In an earlier development effort,
-the tab stop initialization provided by \fBtset\fP(1) (1982),
-and incorporated into \fBtput\fP(1) uses the terminal database,
+By this time,
+System\ V
+.I tput
+had incorporated the tab stop initialization feature of BSD's
+.I tset
+from 1982,
+but employed the
+.I \%term\%info
+database to do so.
 .PP
-The \fB+m\fP option was documented in the POSIX
-Base Specifications Issue 5
+The
+.B +m
+option was documented in the POSIX Base Specifications Issue 5
 (Unix98, 1997),
 then omitted in Issue 6
 (Unix03, 2004)
 without express motivation,
 though an introductory comment
-\fI\*(``and optionally adjusts the margin\*(''\fP remains,
+\*(``and optionally adjusts the margin\*('' remains,
 overlooked in the removal.
-The \fBtabs\fP utility documented in Issues 6 and later has no mechanism
-for setting margins.
-The \fB+m\fP option in
-.I \%ncurses
-\fBtabs\fP differs from the SVr4 feature by using terminal capabilities
+The
+.I tabs
+utility documented in Issues 6 and later has no mechanism for setting
+margins.
+The
+.B +m
+option in
+.IR \%ncurses 's
+implementation
+differs from the SVr4 feature by using terminal capabilities
 rather than built-in tables.
 .PP
 POSIX documents no limit on the number of tab stops.
 Other implementations impose one;
-the limit is 20 in PWB/Unix's \fBtabs\fP utility.
+the limit is 20 in PWB/Unix's
+.I tabs
+utility.
 While some terminals may not accept an arbitrary number of tab stops,
 .I \%ncurses
-\fBtabs\fP attempts to set tab stops up to the right margin if the list
-thereof is sufficiently long.
+attempts to set tab stops up to the right margin
+if the list thereof is sufficiently long.
 .PP
-The \*(``Rationale\*('' section of the Issue 6 \fBtabs\fP reference page
+The \*(``Rationale\*('' section of the Issue 6
+.I tabs
+reference page
 .\" https://pubs.opengroup.org/onlinepubs/009604499/utilities/tabs.html
-details how the committee considered redesigning the \fBtabs\fP and
-\fBtput\fP utilities,
+details how the committee considered redesigning the
+.I tabs
+and
+.I tput
+utilities,
 without settling on an improved solution.
 It claims that
-.RS 5
 .PP
-no known historical version of tabs supports the capability of setting
-arbitrary tab stops.
+.RS 4
+no known historical version of
+.I tabs
+supports the capability of setting arbitrary tab stops.
 .RE
 .PP
-Nevertheless,
-the feature described in subsection \*(``Explicit Lists\*('' above was
+The feature described in subsection \*(``Explicit Lists\*('' above was
 implemented in PWB/Unix,
-and permits the setting of abitrary tab stops.
+.\" see URL above
+and permitted the setting of abitrary tab stops nevertheless.
 .SH SEE ALSO
 \fB\%@INFOCMP@\fP(1M),
 \fB\%@TSET@\fP(1),