chiang@m2c.ORG (Rit Chiang) (02/19/88)
I am currently implementing SCCS in our organization. I have learned all
I can learn from the Dec Ultrix manuals ... I would like to find out
your experiences with SCCS.
Also, I have a few questions and hopefully SCCS and Unix guru could answer.
1) Since SCCS would not let you do hierarchy, is there anything out
there that can traverse the tree structure of SCCS directories. I have
implemented a recursive csh script that would take any SCCS commands
and traverse down the tree. However, I have noticed the performance
is awful.
2) Has anyone implemented anything on top of SCCS, such as report generation,
storage of non-ASCII files, and the likes.
3) Is there any good references besides Intro to SCCS, that could
provide me with a better understanding on how organization utilized SCCS
in their development environment.
I will appreciate any response from any of you gurus out there.
---------------------------------------------------------------------
Rit Chiang
Massachusetts Microelectronics Center
75 North Drive.,
Westboro, MA 01581
(617)870-0312
UUCP : {harvard, ulowell}!m2c!chiang
Internet: chiang@m2c.org
CSNET: chiang%m2c.org@relay.cs.netbd@hpsemc.HP.COM (bob desinger) (03/02/88)
Rit Chiang (chiang@m2c.ORG) writes: > 1) Since SCCS would not let you do hierarchy, is there anything out > there that can traverse the tree structure of SCCS directories. I have > implemented a recursive csh script that would take any SCCS commands > and traverse down the tree. However, I have noticed the performance > is awful. The csh may be dragging you down; scripts written in csh start up more slowly and are more sluggish to respond to signals than /bin/sh or ksh scripts. Try rewriting it in sh (or ksh if you have that). It's possible that the script's algorithm may be slow, too, but fixing that would require a lot of testing to see what your shell can do quickly, followed by a rewrite of the slowest parts. Rewriting may involve C instead of shell, which takes much longer but offers better measurement tools (prof or gprof). A more deep-seated problem may be your file system's performance. If a simple `find {sccs-directories} -print' command seems slow, file system accesses are slow and rewriting your scripts will probably be pointless. Fixing this can be painful. You might get a minor tune-up (improving file system access speed by about 5% or less) via a full backup of the filesystem followed by a newfs [or mkfs, depending on your Unix implementation] and then a restore. But your root-person or admin staff won't be keen to do this because it's time-consuming, it's dangerous, it wears off after a while, and 5% is a pretty meager improvement even if you get that much. > 2) Has anyone implemented anything on top of SCCS, such as report generation, > storage of non-ASCII files, and the likes. Report generation is typically done with shell scripts that call prs(1) and awk or sed. This is SCCS's biggest advantage over RCS: prs can reveal astonishing details about what changed or how much. Storage of non-ASCII (really, "unprintable") files will be hard to do without pre-processing, since SCCS uses a leading control-A on some lines to maintain history and administrative data. Control-A is value "1", which tends to occur pretty often in binary data. According to Kernighan and Pike's _The_Unix_Programming_Environment_, SCCS uses the diff program. Using diff on binaries is, er, unwieldy. > 3) Is there any good references besides Intro to SCCS, that could > provide me with a better understanding on how organization utilized SCCS > in their development environment. If you know anyone who has an HP-UX system, borrow their _HP-UX_ _Concepts_and_Tutorials:_Programming_Environment_ manual and look in the SCCS section. Starting on page 41, the section on "Using SCCS on a Multi-User Project" explains one scheme and shows some code to help you get started administering a project. Intermediate Unix programming classes usually touch on SCCS, too. I'm surprised that there's no Nutshell Handbook about SCCS, although the Handbook on `make' mentions it briefly. If you get any good answers by mail, please summarize to the net! bob desinger bd%hpsemc@hplabs.HP.COM