1tabs(1) General Commands Manual tabs(1)
2
6 tabs - set tabs on a terminal
7
9 tabs [options]] [tabstop-list]
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12 The tabs program clears and sets tab-stops on the terminal. This uses
13 the terminfo clear_all_tabs and set_tab capabilities. If either is
14 absent, tabs is unable to clear/set tab-stops. The terminal should be
15 configured to use hard tabs, e.g.,
16 stty tab0
18 Like clear(1), tabs writes to the standard output. You can redirect
20 the standard output to a file (which prevents tabs from actually chang‐
21 ing the tabstops), and later cat the file to the screen, setting tab‐
22 stops at that point.
23
25 General Options
26 -Tname
27 Tell tabs which terminal type to use. If this option is not
28 given, tabs will use the $TERM environment variable. If that is
29 not set, it will use the ansi+tabs entry.
30 -d The debugging option shows a ruler line, followed by two data
32 lines. The first data line shows the expected tab-stops marked
33 with asterisks. The second data line shows the actual tab-stops,
34 marked with asterisks.
35 -n This option tells tabs to check the options and run any debugging
37 option, but not to modify the terminal settings.
38 -V reports the version of ncurses which was used in this program, and
40 exits.
41 The tabs program processes a single list of tab stops. The last option
43 to be processed which defines a list is the one that determines the
44 list to be processed.
45 Implicit Lists
47 Use a single number as an option, e.g., “-5” to set tabs at the given
48 interval (in this case 1, 6, 11, 16, 21, etc.). Tabs are repeated up
49 to the right margin of the screen.
50 Use “-0” to clear all tabs.
52 Use “-8” to set tabs to the standard interval.
54 Explicit Lists
56 An explicit list can be defined after the options (this does not use a
57 “-”). The values in the list must be in increasing numeric order, and
58 greater than zero. They are separated by a comma or a blank, for exam‐
59 ple,
60 tabs 1,6,11,16,21
62 tabs 1 6 11 16 21
63 Use a “+” to treat a number as an increment relative to the previous
65 value, e.g.,
66 tabs 1,+5,+5,+5,+5
68 which is equivalent to the 1,6,11,16,21 example.
70 Predefined Tab-Stops
72 X/Open defines several predefined lists of tab stops.
73 -a Assembler, IBM S/370, first format
75 -a2 Assembler, IBM S/370, second format
77 -c COBOL, normal format
79 -c2 COBOL compact format
81 -c3 COBOL compact format extended
83 -f FORTRAN
85 -p PL/I
87 -s SNOBOL
89 -u UNIVAC 1100 Assembler
91
93 IEEE Std 1003.1/The Open Group Base Specifications Issue 7
94 (POSIX.1-2008) describes a tabs utility. However
95 · This standard describes a +m option, to set a terminal's left-mar‐
97 gin. Very few of the entries in the terminal database provide this
98 capability.
99 · There is no counterpart in X/Open Curses Issue 7 for this utility,
101 unlike tput(1).
102 The -d (debug) and -n (no-op) options are extensions not provided by
104 other implementations.
105 Documentation for other implementations states that there is a limit on
107 the number of tab stops. While some terminals may not accept an arbi‐
108 trary number of tab stops, this implementation will attempt to set tab
109 stops up to the right margin of the screen, if the given list happens
110 to be that long.
111
113 tset(1), infocmp(1M), curses(3X), terminfo(5).
114 This describes ncurses version 6.1 (patch 20180923).
116 tabs(1)