A sharing lock.
The status of the process while the lock is locked, as seen in the Process Browser.
A timeout period, in seconds.
The forms to execute
with-exclusive-lock is the same as with-lock, except that the lock must be "sharing", that is, created with the argument sharing true in make-lock. It waits until sharing-lock is completely free, that is, the lock is not locked in a sharing mode and is not locked in exclusive mode by another thread. It then locks the lock sharing-lock in exclusive mode, evaluates body and unlocks the lock.
It is not possible to use an exclusive lock in the scope of a sharing-lock on the same lock, and trying to do it will cause the process to hang. Whether it is possible to use exclusive-lock inside exclusive-lock of the same lock is determined by the recursivep argument in make-lock.
LispWorks User Guide and Reference Manual - 13 Feb 2015