comb(1)

comb -- combine SCCS deltas

Synopsis

   comb [-o] [-s] [-pSID] [-clist] file . . .

Description

comb generates a shell procedure [see sh(1)] that, when run, reconstructs the given SCCS files. The reconstructed files are typically 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 path name 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 argument is explained as if only one named file is to be processed, but the effects of any keyletter argument apply independently to each named file.

-o

For each get -e, 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. 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 procedure that, when run, produces a report that gives for each file: the file name, size (in blocks) after combining, original size (also in blocks), and percentage change computed by:

100

(original - combined) / original

It is recommended that before any SCCS files are actually combined, one should use this option to determine exactly how much space is saved by the combining process.

-pSID

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

-c list

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

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

Files

s.COMB: the reconstructed SCCS file
comb?????: temporary file
/usr/lib/locale/locale/LC_MESSAGES/uxepu: language-specific message file (See LANG on environ(5).)

References

admin(1), delta(1), get(1), help(1), prs(1), sccsfile(4), sh(1)

Diagnostics

Use help(1) for explanations.

Notices

comb may rearrange the shape of the tree of deltas.

comb may not save any space; in fact, it is possible for the reconstructed file to be larger than the original.