CVS bug - invalid change text

[ulrich_straub]

Hi CVS gurus,

(1)
In a large project (hundreds of files)
I cannot checkout earlier versions (tags) any more.
I have used the command

cvs co -r <tag> <project_name>

The checkout process is aborted middle in the checkout process
with the error message

"cvs [server aborted]: invalid change text /xxx/xxx/messagehandlers.c,v"

I can retrieve only half of the files.
Fortunately I am still able to check out the current versions of the files.

(2)
Questions:

- what is causing this problem ?
- is it possible to force CVS to continue the checkout without deleteing
the file "messagehandlers.c,v" in the cvs repository ?
- is it possible to repair this file "messagehandlers.c,v" in the
repository ?
- is it possible to avoid such problems in the future ?
- does CVS check the integrity of the repository before and/or after a
commit ?
- if not is there a possibility to force CVS to do such a check ?

(3)
Principal questions:

This problem raises the question whether CVS can be used at all for
serious version management.

It seems CVS is able to corrupt older versions of a file by commits carried
out at some later point in time.
(that is what has actually happened).

It seems that this could happen unnoticed (there were no warnings that
the file  "messagehandlers.c,v" became corrupt).
It also seems that the problem is restricted to parts of the files only
(since the current version can be checked out successfully).

This also means that it is impossible for a user to determine by simple
means
whether the data in the CVS repository are still valid or became invalid in
the meantime.

And this in turn would mean that one needs to save every version of a file
independently
just in case CVS might not give you back the old files.

Mit freundlichen Gruessen / With kind regards
           Ulrich Straub

E-mail:  address@hidden
Tel:  (+49)-7031-16-2884 , Fax -3619