AT&T UNIX™PC Unix System V Users Manual - tenox

SEMOP (2) SEMOP (2)
Operation permission is denied to the calling process (see
intro(2)). IEACCES]
The operation would result in suspension of the calling
process but (sem_flg & IPC_NO\VAIT) is "true".
lEA GAIN]
The limit on the number of individual processes requesting
an SEM_UNDO would be exceeded. IENOSPC]
The number of individual semaphores for which the calling
process requests a SEM_UNDO would exceed the
limit. IEINV AL]
An operation would cause a semval to overflow the system
imposed limit. IERANGE]
An operation would cause a semadj value to overflow the
system imposed limit. IERANGE]
Sops points to an illegal address. IEFAULT]
Upon successful completion, the value of sempid for each semaphore
specified in the array pointed to by sops is set equal to the
process ID of the calling process.
RETURN VALUE
If semop returns due to the receipt of a signal, a value of -1 is
returned to the calling process and errno is set to EINTR. If it
returns due to the removal of a semid from the system, a value of
-1 is returned and errno is set to EIDRM.
Upon successful completion, the value of semval at the time of the
call for the last operation in the array pointed to by sops is
returned. Otherwise, a value of -1 is returned and errno is set to
indicate the error.
SEE ALSO
exec(2), exit(2), fork(2), semct1(2), semget(2), stdipc(3C).
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