0 Successful completion. The function executes
the semaphore unlink operation.
-1 Indicates an error. The function sets errno to
one of the following values:
o EACCESS - Permission is denied to unlink
the named semaphore.
o ENAMETOOLONG - The length of the path
name exceeds PSEM_MAX_PATHNAME defined
in semaphore.h.
o ENOENT - The named semaphore does not
exist.
o EVMSERR - OpenVMS specific nontranslatable
error code.