Unlike some other implementations of sccs, cssc tools do not
usually execute each other. This means for example that delta
does not invoke get to extract the previous version of the file,
and prs doesn't use get when processing the :GB:
keyword.
There are a small number of exceptions to this rule :-
sccssccs driver program can be used to invoke any of the other
tools in the suite. See Known Problems, for a discussion of the
issues this raises.
deltadelta program runs a program to validate the Modification
Request Numbers offered by the user. See Modification Request Numbers.
sccsdiffsccsdiff program is a shell script, and invokes
get, diff and pr, as well as other tools such as
cat, test and rm. The sccsdiff program must
not be installed set-user-id.
The driver program sccs takes a number of precautionary steps
if it detects that it is running set-user-id or set-group-id. These
steps are described below, as part of the discussion of each
environment variable.