X-Git-Url: https://ncurses.scripts.mit.edu/?p=ncurses.git;a=blobdiff_plain;f=doc%2Fhtml%2Fman%2Ftabs.1.html;h=e8c8e70049add0a0a478c6d078c173ac6005feab;hp=7657407597e7d2446feafd40e30d0248b22c60ff;hb=9f479192e3ca3413d235c66bf058f8cc63764898;hpb=a20e6eb464be80b9cd8cae7ce925d27fe9c209ed diff --git a/doc/html/man/tabs.1.html b/doc/html/man/tabs.1.html index 76574075..e8c8e700 100644 --- a/doc/html/man/tabs.1.html +++ b/doc/html/man/tabs.1.html @@ -1,6 +1,7 @@ - - -tabs 1 - + +@TABS@ 1 + -

tabs 1

+

@TABS@ 1

-tabs(1)                                                                tabs(1)
+tabs(1)                     General Commands Manual                    tabs(1)
 
 
 
 
 

NAME

-       tabs - set tabs on a terminal
+       tabs - set tabs on a terminal
 
 
 

SYNOPSIS

-       tabs [options]] [tabstop-list]
+       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
+       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
+           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.
+       Like clear(1), tabs writes to the standard output.   You  can  redirect
+       the  standard  output  to  a  file  (which  prevents tabs from actually
+       changing the tabstops), and later cat the file to the  screen,  setting
+       tabstops at that point.
+
+       These   are   hardware   tabs,  which  cannot  be  queried  rapidly  by
+       applications running in the terminal, if  at  all.   Curses  and  other
+       full-screen  applications  may  use  hardware  tabs in optimizing their
+       output to the terminal.  If  the  hardware  tabstops  differ  from  the
+       information  in  the  terminal  database,  the result is unpredictable.
+       Before running curses programs, you should either  reset  tab-stops  to
+       the standard interval
+
+           tabs -8
+
+       or  use the reset program, since the normal initialization sequences do
+       not ensure that tab-stops are reset.
 
 
 

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,
+       -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
+       -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
+       -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
+       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
+       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 "-0" to clear all tabs.
 
-       Use "-8" to set tabs to the standard interval.
+       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,
+       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
+       example,
 
-         tabs 1,6,11,16,21
-         tabs 1 6 11 16 21
+           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
+       Use a "+" to treat a number as an increment relative  to  the  previous
        value, e.g.,
 
-         tabs 1,+5,+5,+5,+5
+           tabs 1,+5,+5,+5,+5
 
        which is equivalent to the 1,6,11,16,21 example.
 
@@ -121,54 +135,83 @@
 

Predefined Tab-Stops

        X/Open defines several predefined lists of tab stops.
 
-       -a   Assembler, IBM S/370, first format
+       -a   Assembler, IBM S/370, first format
 
-       -a2  Assembler, IBM S/370, second format
+       -a2  Assembler, IBM S/370, second format
 
-       -c   COBOL, normal format
+       -c   COBOL, normal format
 
-       -c2  COBOL compact format
+       -c2  COBOL compact format
 
-       -c3  COBOL compact format extended
+       -c3  COBOL compact format extended
 
-       -f   FORTRAN
+       -f   FORTRAN
 
-       -p   PL/I
+       -p   PL/I
 
-       -s   SNOBOL
+       -s   SNOBOL
 
-       -u   UNIVAC 1100 Assembler
+       -u   UNIVAC 1100 Assembler
 
 
 

PORTABILITY

-       IEEE  Std  1003.1/The  Open  Group    Base   Specifications   Issue   7
-       (POSIX.1-2008) describes a tabs utility.  However
+       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   This standard describes a +m option,  to  set  a  terminal's  left-
+           margin.   Very  few of the entries in the terminal database provide
+           the  smgl   (set_left_margin)   or   smglp   (set_left_margin_parm)
+           capability needed to support the feature.
 
-       o   There  is no counterpart in X/Open Curses Issue 7 for this utility,
-           unlike tput(1).
+       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
+       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.
+       A  tabs  utility  appeared in PWB/Unix 1.0 (1977).  There was a reduced
+       version of the tabs 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.
+
+       The PWB/Unix tabs 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.
+
+       Later versions of Unix, e.g., SVr4,  added  support  for  the  terminal
+       database,   but  kept  the  tables,  as  a  fallback.   In  an  earlier
+       development effort, the tab-stop initialization provided by tset (1982)
+       and incorporated into tput uses the terminal database,
+
+       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 (e.g., 20 in PWB/Unix's tabs 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.
+
+       The Rationale section of the POSIX documentation goes into some  detail
+       about  the  ways the committee considered redesigning the tabs and tput
+       utilities, without proposing an improved solution.  It comments that
+
+            no known historical version of tabs  supports  the  capability  of
+            setting arbitrary tab stops.
+
+       However,  the  Explicit  Lists  described  in  this  manual  page  were
+       implemented in PWB/Unix.   Those  provide  the  capability  of  setting
+       abitrary tab stops.
 
 
 

SEE ALSO

-       tset(1), infocmp(1m), curses(3x), terminfo(5).
+       infocmp(1M), tset(1), curses(3X), terminfo(5).
 
-       This describes ncurses version 6.0 (patch 20170812).
+       This describes ncurses version 6.2 (patch 20210612).
 
 
 
-                                                                       tabs(1)
+                                                                       tabs(1)