comb(1) comb(1)NAME comb - combine SCCS deltas SYNOPSIS comb [-clist] [-o] [-psid] [-s] file ... 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, hope- fully, 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 un- readable 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 ef- fects 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 dis- carded in the reconstructed file. -clist A list (see get(1) for the syntax of a list) of del- tas to be preserved. All other deltas are discard- ed. -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 A/UX 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 per- centage change computed by: April, 1990 1
comb(1) comb(1)100 * (original - combined) / original It is recommended that before any SCCS files are ac- tually 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. EXAMPLES 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 A/UX 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 recon- structed file actually to be larger than the original. 2 April, 1990