(cvs.info.gz) Concurrency
Info Catalog
(cvs.info.gz) Informing others
(cvs.info.gz) Multiple developers
(cvs.info.gz) Watches
10.5 Several developers simultaneously attempting to run CVS
============================================================
If several developers try to run CVS at the same time, one may get the
following message:
[11:43:23] waiting for bach's lock in /usr/local/cvsroot/foo
CVS will try again every 30 seconds, and either continue with the
operation or print the message again, if it still needs to wait. If a
lock seems to stick around for an undue amount of time, find the person
holding the lock and ask them about the cvs command they are running.
If they aren't running a cvs command, look in the repository directory
mentioned in the message and remove files which they own whose names
start with `#cvs.rfl', `#cvs.wfl', or `#cvs.lock'.
Note that these locks are to protect CVS's internal data structures
and have no relationship to the word "lock" in the sense used by
RCS--which refers to reserved checkouts ( Multiple developers).
Any number of people can be reading from a given repository at a
time; only when someone is writing do the locks prevent other people
from reading or writing.
One might hope for the following property:
If someone commits some changes in one cvs command, then an update
by someone else will either get all the changes, or none of them.
but CVS does _not_ have this property. For example, given the files
a/one.c
a/two.c
b/three.c
b/four.c
if someone runs
cvs ci a/two.c b/three.c
and someone else runs `cvs update' at the same time, the person running
`update' might get only the change to `b/three.c' and not the change to
`a/two.c'.
Info Catalog
(cvs.info.gz) Informing others
(cvs.info.gz) Multiple developers
(cvs.info.gz) Watches
automatically generated byinfo2html