comb(1)                                                   comb(1)



     NAME
          comb - combine SCCS deltas

     SYNOPSIS
          comb [-clist] [-o] [-psid] [-s] files

     DESCRIPTION
          comb generates a shell script (see sh(1)) which, when run,
          will reconstruct the given SCCS files by combining some
          series of changes.  Then the reconstructed files will,
          hopefully, be smaller than the original files.  The
          arguments may be specified in any order, but all keyletter
          arguments apply to all named SCCS files.  If a directory is
          named, comb behaves as though each file in the directory
          were specified as a named file, except that non-SCCS files
          (last component of the pathname does not begin with s.) and
          unreadable files are silently ignored.  If a name of - is
          given, the standard input is read; each line of the input is
          taken to be the name of an SCCS file to be processed; non-
          SCCS files and unreadable files are silently ignored.

          The generated shell procedure is written on the standard
          output.

          The keyletter arguments are as follows (each is explained as
          though only one named file is to be processed, but the
          effects of any keyletter argument apply independently to
          each named file):

          -pSID    The SCCS Identification string (SID) of the oldest
                  delta to be preserved.  All older deltas are
                  discarded in the reconstructed file.

          -clist  A list (see get(1) for the syntax of a list) of
                  deltas to be preserved.  All other deltas are
                  discarded.

          -o      For each get -e generated, this argument causes the
                  reconstructed file to be accessed at the release of
                  the delta to be created, otherwise the reconstructed
                  file would be accessed at the most recent ancestor
                  (see ``SCCS Reference'' in Oreo Programming
                  Languages and Tools, Volume 2).  Use of the -o
                  keyletter may decrease the size of the reconstructed
                  SCCS file.  It may also alter the shape of the delta
                  tree of the original file.

          -s      This argument causes comb to generate a shell script
                  which, when run, will produce a report giving, for
                  each file: the filename, size (in blocks) after
                  combining, original size (also in blocks), and
                  percentage change computed by:



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     comb(1)                                                   comb(1)



                         100 * (original - combined) / original
                  It is recommended that before any SCCS files are
                  actually combined, one should use this flag option
                  to determine exactly how much space is saved by the
                  combining process.

          If no keyletter arguments are specified, comb will preserve
          only leaf deltas and the minimal number of ancestors needed
          to preserve the tree.

     EXAMPLE
               comb s.file1 > tmp1

          produces a shell script saved in tmp1 which will remove from
          the SCCS-format file, s.file1, all deltas previous to the
          last set of changes, i.e., removes the capability to return
          to earlier versions.

     FILES
          /usr/bin/comb

          s.COMB         The name of the reconstructed SCCS file.

          comb?????      Temporary.

     SEE ALSO
          admin(1), delta(1), get(1), help(1), prs(1), sh(1),
          sccsfile(4).
          ``SCCS Reference'' in Oreo Programming Languages and Tools,
          Volume 2.

     DIAGNOSTICS
          Use help(1) for explanations.

     BUGS
          comb may rearrange the shape of the tree of deltas.  It may
          not save any space; in fact, it is possible for the
          reconstructed file actually to be larger than the original.

















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