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process-lock

Function
Summary

Claims the lock for the current process.

Package

mp

Signature

process-lock lock &optional whostate timeout => bool

Arguments

lock

A lock object (see make-lock).

whostate

The status of the current Lisp process, before process-lock returns, that is, the status while the current process is waiting to timeout. This can be seen in the Process Browser.

timeout

A timeout interval, in seconds. If this is not given, process-lock waits until the lock can be set by the current Lisp process. A process can set a lock more than once.

Values

bool

t if the process was successfully locked; nil otherwise.

Description

process-lock attempts to set a lock and returns t if successful, or nil if timed out. If the lock is set and the owner of the lock is the value of *current-process* , then the lock's count is incremented by 1, and the lock is set to t . The Lisp process sleeps until the lock is claimed or the timeout period expires.

Example

(process-lock *my-lock* "waiting to lock" 10)

See also
claim-lock
make-lock
process-unlock
release-lock
with-lock

LispWorks Reference Manual - 13 Jun 2003

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