How do I lock a file in Perl?

Question

What is the best way to create a lock on a file in Perl?

Is it best to flock on the file or to create a lock file to place a lock on and check for a lock on the lock

Answer 1

flock creates Unix-style file locks, and is available on most OS's Perl runs on. However flock's locks are advisory only.

edit: emphasized that flock is portable