Removes a sharing lock.
The function process-sharing-unlock is the same as process-unlock but for a "sharing" lock.
Calls to process-sharing-unlock should be matched by calls to process-sharing-lock with sharing-lock. Normally with-sharing-lock is the best way to achieve this.
process-sharing-unlock is guaranteed to successfully unlock sharing-lock, but is not guaranteed to return, as described in Guarantees and limitations when locking and unlocking.
LispWorks User Guide and Reference Manual - 20 Sep 2017