ncurses 6.2 - patch 20211009

[ncurses.git] / man / tabs.1

diff --git a/man/tabs.1 b/man/tabs.1
index de47222592fa4b81c527a7436a7845aa0403e1d8..822e677b975a708fcd0d1f4e3c47e33aad93e88a 100644 (file)
--- a/man/tabs.1
+++ b/man/tabs.1
@@ -1,5 +1,6 @@
 .\"***************************************************************************
-.\" Copyright (c) 2008-2018,2019 Free Software Foundation, Inc.              *
+.\" Copyright 2018-2020,2021 Thomas E. Dickey                                *
+.\" Copyright 2008-2016,2017 Free Software Foundation, Inc.                  *
 .\"                                                                          *
 .\" Permission is hereby granted, free of charge, to any person obtaining a  *
 .\" copy of this software and associated documentation files (the            *
@@ -26,7 +27,7 @@
 .\" authorization.                                                           *
 .\"***************************************************************************
 .\"
-.\" $Id: tabs.1,v 1.25 2019/06/15 23:08:12 tom Exp $
+.\" $Id: tabs.1,v 1.30 2021/10/09 23:48:50 tom Exp $
 .TH @TABS@ 1 ""
 .ds n 5
 .ie \n(.g .ds `` \(lq
@@ -139,34 +140,78 @@ tabs 1,+5,+5,+5,+5
 .PP
 which is equivalent to the 1,6,11,16,21 example.
 .SS Predefined Tab-Stops
-X/Open defines several predefined lists of tab stops.
+POSIX defines several predefined lists of tab stops.
 .TP 5
 .B \-a
 Assembler, IBM S/370, first format
+.br
+1,10,16,36,72
 .TP 5
 .B \-a2
 Assembler, IBM S/370, second format
+.br
+1,10,16,40,72
 .TP 5
 .B \-c
 COBOL, normal format
+.br
+1,8,12,16,20,55
 .TP 5
 .B \-c2
 COBOL compact format
+.br
+1,6,10,14,49
 .TP 5
 .B \-c3
 COBOL compact format extended
+.br
+1,6,10,14,18,22,26,30,34,38,42,46,50,54,58,62,67
 .TP 5
 .B \-f
 FORTRAN
+.br
+1,7,11,15,19,23
 .TP 5
 .B \-p
 PL/I
+.br
+1,5,9,13,17,21,25,29,33,37,41,45,49,53,57,61
 .TP 5
 .B \-s
 SNOBOL
+.br
+1,10,55
 .TP 5
 .B \-u
 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:
+.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.
+.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.
+.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.
+.PP
+When setting or resetting the left-margin,
+@TABS@ may reset the right-margin.
 .SH PORTABILITY
 .PP
 \fIIEEE Std 1003.1/The Open Group Base Specifications Issue 7\fP (POSIX.1-2008)
@@ -180,17 +225,20 @@ Very few of the entries in the terminal database provide the
 capability needed to support the feature.
 .bP
 There is no counterpart in X/Open Curses Issue 7 for this utility,
-unlike \fB@TPUT@(1)\fP.
+unlike \fB@TPUT@\fP(1).
 .PP
 The \fB\-d\fP (debug) and \fB\-n\fP (no-op) options are extensions not provided
 by other implementations.
 .PP
-A \fBtabs\fP utility appeared in PWB/Unix 1.0 (1977),
-and thereafter in 3BSD (1979).
-It supported a single \*(``\-n\*('' option
+A \fBtabs\fP utility appeared in PWB/Unix 1.0 (1977).
+There was a reduced version of the \fBtabs\fP utility
+in Unix 7th edition and in 3BSD (1979).
+The latter supported a single \*(``\-n\*('' option
 (to cause the first tab stop to be set on the left margin).
 That option is not documented by POSIX.
-Initially, \fBtabs\fP used built-in tables rather than the terminal database,
+.PP
+The PWB/Unix \fBtabs\fP utility, which was included in System III (1980),
+used built-in tables rather than the terminal database,
 to support a half-dozen terminal types.
 It also had built-in logic to support the left-margin,
 as well as a feature for copying the tab settings from a file.
@@ -204,7 +252,8 @@ and incorporated into \fBtput\fP uses the terminal database,
 .PP
 POSIX documents no limits on the number of tab stops.
 Documentation for other implementations states that there is a limit on the
-number of tab stops.
+number of tab stops
+(e.g., 20 in PWB/Unix's \fBtabs\fP utility).
 While some terminals may not accept an arbitrary number
 of tab stops, this implementation will attempt to set tab stops up to the
 right margin of the screen, if the given list happens to be that long.
@@ -224,8 +273,8 @@ However, the \fIExplicit Lists\fP described in this manual page
 were implemented in PWB/Unix.
 Those provide the capability of setting abitrary tab stops.
 .SH SEE ALSO
-\fB@TSET@\fR(1),
 \fB@INFOCMP@\fR(1M),
+\fB@TSET@\fR(1),
 \fBcurses\fR(3X),
 \fBterminfo\fR(\*n).
 .PP