On Sat, 15 Jul 2006 23:52:10 +0200, Sybren Stuvel wrote: > Elmo Mäntynen enlightened us with: >> Only locally. I want to be able to read/write to a single file from >> multiple possibly parallel processes. Would 'touch lock' (or >> something like that) work reliably (this just occured to me)? > > I use a lock directory for that, os.mkdir('/var/lock/somedir'). > If you use a file, you need two steps: > 1) Check whether the lock-file exists > 2) Create the lock-file > > This is not atomic. With a directory, creating it will fail if it > already exists. This means you can atomically check for the lock, and > if it doesn't exist already, you've immediately created it too. > > Sybren
Thanks. Is that what atomic basically means? -- http://mail.python.org/mailman/listinfo/python-list