Locks are simply a file saying that a particular device is in use.
They are kept in /usr/spool/uucp
. Locks are named
LCK..<name>
, where <name>
is either a device name,
or a UUCP site name. Certain processes create these locks so that
they can have exclusive access to devices, for instance if you dial
out on your modem, a lock will appear telling other processes that
someone is using the modem already. Locks mainly contain the PID
of the process that has locked the device. Most programs look at
the lock, and try to determine if that lock is still valid by checking
the process table for the process that has locked the device. If the
lock is found to be valid, the program should exit.
If not, some programs remove the stale lock, and use the device,
creating their own lock in the process.
Next Chapter, Previous Chapter
Table of contents of this chapter, General table of contents
Top of the document, Beginning of this Chapter