write to the same file from multiple processes at the same time?

[Paul Rubin]

Jp Calderone <exarkun at divmod.com> writes:
> >But they haven't.  They depend on messy things like server processes
> >constantly running, which goes against the idea of a cgi that only
> >runs when someone calls it.
> 
> SQLite is an in-process dbm.

http://www.sqlite.org/faq.html#q7

    (7) Can multiple applications or multiple instances of the same
    application access a single database file at the same time?

    Multiple processes can have the same database open at the same
    time. Multiple processes can be doing a SELECT at the same
    time. But only one process can be making changes to the database
    at once.

But multiple processes changing the database simultaneously is
precisely what the OP wants to do.