A/UX® Programmer's Reference

intro(2) intro(2)
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structure includes the following members:
ushort cuid; /* creator user ID */
ushort cgid; /* creator group ID */
ushort uid; /* user ID */
ushort gid; /* group ID */
ushort mode; /* ria permission */
The value of sern nserns is equal to the number of semaphores
in the set Each semaphore in the set is referenced by a positive
integer referred to as a sern num. sern num values run sequentially
from 0 to the value ofsern nserns minus 1. sern otirne
is the time of the last sernop(2) operation, and sern ctirne is
the time of the last sernctl(2) operation that changed a member
of the structure described earlier.
A semaphore is a data structure that contains the following
members:
ushort semval; /* semaphore value */
short sempid; /* pid of last operation */
ushort semncnt; /* # awaiting semval > cval */
ushort semzcnt; /* # awaiting semval = 0 */
sernval is a non-negative integer. sernpid is equal to the process
ID of the last process that performed a semaphore operation
on this semaphore. sernncnt is a count of the number of
processes that are currently suspended and awaiting this
semaphore's sernval to become greater than its current value.
sernzcnt is a count of the number of processes that are currently
suspended awaiting this semaphore's sernval to become O.
Shared Memory Identifier
A shared memory identifier (shmid) is a unique positive integer
created by a shrnget(2) system call. Each shmid has a segment
of memory (referred to as a shared memory segment) and a data
structure associated with it. The data structure referred to as
shrnid _ ds contains the following members:
struct ipc_perm shm_perm; /* operation permission struct */
int shm_segsz; /* size of segment */
ushort shm_cpid; /* creator pid */
ushort shm lpid; /* pid of last operation */
short shm=nattch; /* number of current attaches */
time
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t
time t
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time
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t
shm atime;
shm=dtime;
shm ctime;
/* last attach time */
/* last detach time */
/* last change time */
/* Times measured in secs
since 00:00:00 GMT, 1/1/70 */
shrn_perrn is an ipcyerrn structure that specifies the shared-
February, 1990
RevisionC