http://invisible-island.net/ncurses/man/


tabs 1

tabs(1)                                                                tabs(1)




NAME

       tabs - set tabs on a terminal


SYNOPSIS

       tabs [options]] [tabstop-list]


DESCRIPTION

       The  tabs program clears and sets tab-stops on the terminal.  This uses
       the terminfo clear_all_tabs and set_tab  capabilities.   If  either  is
       absent,  tabs is unable to clear/set tab-stops.  The terminal should be
       configured to use hard tabs, e.g.,

         stty tab0

       Like clear(1), tabs writes to the standard output.   You  can  redirect
       the standard output to a file (which prevents tabs from actually chang-
       ing the tabstops), and later cat the file to the screen,  setting  tab-
       stops at that point.


OPTIONS


General Options

       -Tname
            Tell  tabs  which  terminal  type  to  use.  If this option is not
            given, tabs will use the $TERM environment variable.  If  that  is
            not set, it will use the ansi+tabs entry.

       -d   The  debugging  option  shows  a  ruler line, followed by two data
            lines.  The first data line shows the  expected  tab-stops  marked
            with  asterisks.  The second data line shows the actual tab-stops,
            marked with asterisks.

       -n   This option tells tabs to check the options and run any  debugging
            option, but not to modify the terminal settings.

       -V   reports the version of ncurses which was used in this program, and
            exits.

       The tabs program processes a single list of tab stops.  The last option
       to  be  processed  which  defines a list is the one that determines the
       list to be processed.


Implicit Lists

       Use a single number as an option, e.g., "-5" to set tabs at  the  given
       interval  (in  this case 1, 6, 11, 16, 21, etc.).  Tabs are repeated up
       to the right margin of the screen.

       Use "-0" to clear all tabs.

       Use "-8" to set tabs to the standard interval.


Explicit Lists

       An explicit list can be defined after the options (this does not use  a
       "-").   The values in the list must be in increasing numeric order, and
       greater than zero.  They are separated by a comma or a blank, for exam-
       ple,

         tabs 1,6,11,16,21
         tabs 1 6 11 16 21

       Use  a  "+"  to treat a number as an increment relative to the previous
       value, e.g.,

         tabs 1,+5,+5,+5,+5

       which is equivalent to the 1,6,11,16,21 example.


Predefined Tab-Stops

       X/Open defines several predefined lists of tab stops.

       -a   Assembler, IBM S/370, first format

       -a2  Assembler, IBM S/370, second format

       -c   COBOL, normal format

       -c2  COBOL compact format

       -c3  COBOL compact format extended

       -f   FORTRAN

       -p   PL/I

       -s   SNOBOL

       -u   UNIVAC 1100 Assembler


PORTABILITY

       IEEE  Std  1003.1/The  Open  Group    Base   Specifications   Issue   7
       (POSIX.1-2008) describes a tabs utility.  However

       o   This  standard describes a +m option, to set a terminal's left-mar-
           gin.  Very few of the entries in the terminal database provide this
           capability.

       o   There  is no counterpart in X/Open Curses Issue 7 for this utility,
           unlike tput(1).

       The -d (debug) and -n (no-op) options are extensions  not  provided  by
       other implementations.

       Documentation for other implementations states that there is a limit on
       the number of tab stops.  While some terminals may not accept an  arbi-
       trary  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.


SEE ALSO

       tset(1), infocmp(1m), curses(3x), terminfo(5).

       This describes ncurses version 6.0 (patch 20171014).



                                                                       tabs(1)