Function MAKE-LOCK
Syntax:
make-lock &key name => lock
Arguments and values:
name -> a string or nil.
lock -> a lock object.
Description:
Creates a non-recursive lock named name.
Exceptional situations:
Signals a condition of type
type-error
if name is neither a string nor nil.
See also:
Notes:
A lock is also commonly known as a mutex.
On some implementations, the host lock type is always recursive.