rcsdiff(1)


NAME

   rcsdiff - compare RCS revisions

SYNOPSIS

   rcsdiff  [  -ksubst  ]  [ -q ] [ -rrev1 [ -rrev2 ] ] [ -T ] [ -V[n] ] [
   -xsuffixes ] [ -zzone ] [ diff options ] file ...

DESCRIPTION

   rcsdiff runs diff(1) to compare two revisions of each RCS file given.

   Filenames matching an RCS suffix denote RCS files;  all  others  denote
   working files.  Names are paired as explained in ci(1).

   The  option  -q  suppresses  diagnostic  output.   Zero,  one,  or  two
   revisions may be specified with -r.  The option -ksubst affects keyword
   substitution  when  extracting  revisions,  as  described in co(1); for
   example, -kk -r1.1 -r1.2 ignores differences  in  keyword  values  when
   comparing  revisions  1.1  and 1.2.  To avoid excess output from locker
   name substitution, -kkvl is assumed if (1) at most one revision  option
   is  given,  (2)  no -k option is given, (3) -kkv is the default keyword
   substitution, and (4) the working file's  mode  would  be  produced  by
   co -l.   See co(1) for details about -T, -V, -x and -z.  Otherwise, all
   options of diff(1) that apply to regular files are accepted,  with  the
   same meaning as for diff.

   If both rev1 and rev2 are omitted, rcsdiff compares the latest revision
   on the default branch (by default the trunk) with the contents  of  the
   corresponding  working  file.   This is useful for determining what you
   changed since the last checkin.

   If rev1 is given, but rev2 is omitted, rcsdiff compares  revision  rev1
   of the RCS file with the contents of the corresponding working file.

   If  both  rev1  and rev2 are given, rcsdiff compares revisions rev1 and
   rev2 of the RCS file.

   Both rev1 and rev2 may be given numerically or symbolically.

EXAMPLE

   The command

           rcsdiff  f.c

   compares the latest revision on the default branch of the RCS  file  to
   the contents of the working file f.c.

ENVIRONMENT

   RCSINIT
          Options  prepended to the argument list, separated by spaces.  A
          backslash escapes spaces within an option.  The RCSINIT  options
          are  prepended  to  the  argument  lists  of  most RCS commands.
          Useful RCSINIT options include -q, -V, -x, and -z.

   RCS_MEM_LIMIT
          Normally, for speed, commands either memory  map  or  copy  into
          memory  the  RCS file if its size is less than the memory-limit,
          currently defaulting to ``unlimited''.   Otherwise  (or  if  the
          initially-tried  speedy  ways  fail),  the commands fall back to
          using standard i/o routines.  You can adjust the memory limit by
          setting  RCS_MEM_LIMIT  to  a  numeric  value  lim  (measured in
          kilobytes).  An empty value is  silently  ignored.   As  a  side
          effect,  specifying  RCS_MEM_LIMIT  inhibits fall-back to slower
          routines.

   TMPDIR Name of the temporary directory.  If not  set,  the  environment
          variables TMP and TEMP are inspected instead and the first value
          found is taken; if  none  of  them  are  set,  a  host-dependent
          default is used, typically /tmp.

DIAGNOSTICS

   Exit  status  is 0 for no differences during any comparison, 1 for some
   differences, 2 for trouble.

IDENTIFICATION

   Author: Walter F. Tichy.
   Manual Page Revision: 5.9.4; Release Date: 2015-06-21.
   Copyright  2010-2015 Thien-Thi Nguyen.
   Copyright  1990, 1991, 1992, 1993 Paul Eggert.
   Copyright  1982, 1988, 1989 Walter F. Tichy.

SEE ALSO

   ci(1), co(1), diff(1), ident(1), rcs(1), rcsmerge(1), rlog(1).

   Walter F. Tichy, RCS--A System for Version Control,  Software--Practice
   & Experience 15, 7 (July 1985), 637-654.

   The  full  documentation for RCS is maintained as a Texinfo manual.  If
   the info(1) and RCS programs are properly installed at your  site,  the
   command

          info rcs

   should  give  you access to the complete manual.  Additionally, the RCS
   homepage:

          http://www.gnu.org/software/rcs/

   has news and links to the latest release, development site, etc.





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