12 Sep
2019
12 Sep
'19
10:45 p.m.
Actually I preferred SCCS for all the reasons that Larry has described.
But SCCS was encumbered --- usable at the university, but not in a
commercial environment --- so it wasn't available at Britton-Lee at a
price we could afford, and RCS was pretty much the only other game in town.
Tichy was comparing against SCCS version 1, as described in the paper
"The source code control system" (Marc Rochkind, IEEE Transactions on
Software Engineering 1, 4, December 1975), which used forward deltas ---
very slow as your history got big. I spent considerable time trying to
convince him that the version of SCCS in current production was as Larry
described, where any version could be read in linear time, but he wasn't
hearing anything that went against his beliefs. So far as I know, he
never even looked at or measured the system he was comparing RCS to.
Today I probably wouldn't use SCCS, mostly because of the atomic update
problem (which was still broken in RCS, but fixed in CVS). At this
point I'm using git because, well, all the cool kids are doing it, and
since I work at the university I have to go with the flow sometimes.
And git has some nice properties. On the other hand, I have shot myself
in the foot with git more times than the sum of all other screwups with
all other source management systems combined.
eric
On 2019-09-11 21:28, Jon Forrest wrote:
I used both RCS and SCCS in the early days (e.g. 1985 - 1991). RCS was
what we used at Britton-Lee in the group that Eric Allman was part of.
SCCS is what we used at Sybase as it was gaining popularity. This was
so long ago that I don't remember all the details but I found that
RCS was much easier to use, especially in an environment that didn't
do much merging. Instead we used labels (or tags, I forget what they
were called) to mark which files were part of which release. Doing
this was much harder in SCCS, which contributed to the mess that
was Sybase software engineering.
Of course, all this could be explained by Eric's deep knowledge
of RCS, and the lack of somebody with Eric's knowledge at Sybase.
But, to me, an early adopter of source code control who wasn't
overly interested in speed, RCS was much easier to use.
Jon