Re: Question about flock and printing to file

As it says in the docs flock :-

locks are merely advisory

Exactly what happens will depend on the operating system you're on, what other process is trying to write to the file, and the exact timing of the writes.

IMHO flock just isn't worth using, it's almost entirely pointless.

Comment on Re: Question about flock and printing to file

Replies are listed 'Best First'.
Re^2: Question about flock and printing to file by afoken (Chancellor) on Jun 23, 2015 at 16:24 UTC
IMHO flock just isn't worth using, it's almost entirely pointless. flock is advisory, that's true. But to conclude that flock is useless is just wrong. flock won't prevent a malicious (or clueless) other process from damaging a file. But as long as all processes agree on using flock to access the file, no damage will happen. Period. Unless, of course, the file is on NFS or other network filesystems (SMB, AFS, ...). At least some versions of NFS have locking problems, other network filesystems may have them, too. Alexander -- Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)	[reply]
Re^3: Question about flock and printing to file by AnomalousMonk (Archbishop) on Jun 23, 2015 at 17:19 UTC
... as long as all processes agree on using flock to access the file, no damage will happen. Period. Unless, of course, ... Unfortunately, Dave, that sounds a lot like Famous Last Words. Give a man a fish: `<%-(-(-(-<`	[reply] [d/l]