File::LockDir For Linux

File::LockDir is a Perl basic filename-level lock utility.

use File::LockDir;

new

Initializes the class. Returns the singleton object.

nflock($file, $nap_till, $locker, $lockhost)

Locks the supplied filename. Only $file is required.

$file is the file to be locked; $nap_till is the total amount of time to wait before giving up; $locker is a name identifying the locker; $lockhost is the host requesting the lock.

nunflock($file)

Unlocks the supplied file.

nlock_state($file)

Checks the state of the lock for the supplied file. Returns a list: the first item is true if the file is unlocked, and false if not; the second item is undef if the file is unlocked, and the identity (name and host) is it is locked.

%s already locked

Seen when you've already locked the requested pathname. Informational only.

No pathname to be locked

You didn't supply a pathname to be locked to nflock. Fatal.

can't write to directory of %s

The directory where the file resides can't be written, so the lockfile can't be created.

can't get %s: %s

The named lock can't be gotten: the reason is supplied. Failure occurs after ten tries to get the lock.

%s %s[%s]: lock on %s held by %s

The lock on the specified file is help by the noted locker. Informatory message, printed only when debugging is on.

close failed for %s: %s

The file containing the lock information couldn't be closed for the reason shown.

releasing lock on %s

Debug message; notes that the lock on the specified file was successfully released.