VC and too long command lines

[Deniz Dogan]

Recently I came across a problem when using VC in Emacs.  I had just 
added a whole bunch of files to my Bazaar repository and wanted to 
commit them all.  I chose to mark them all in vc-dir and then tried to 
commit them.

However...

File error: "Spawning child process", "exec format error"

Of course, the command line was simply too long (approximately 66,000 
characters) for my operating system to handle (Windows 7 64-bit).

What should Emacs do when this happens?

I think the most appropriate thing would be to add some functionality 
which determines the maximum command line length for the current system 
and if the call exceeds that length, tell the user about it.  Another 
way would be to e.g. divide the commit into several smaller commits and 
appending something along the lines of "(commit N of M)" to each commit 
message.

What do you think?  I think this is quite an important issue.

Deniz