A/UX® Programmer's Reference

intro(2) intro(2)
memory-operation pennlsslon (described later in this section).
This structure includes the following members:
ushort cuid;
ushort cgid;
ushort uid;
ushort gid;
ushort mode;
/* creator user IO */
/* creator group IO */
/* user IO */
/* group IO */
/* r/w permission */
shm_segsz specifies the size of the shared memory segment.
shm _ cpid is the process ID of the process that created the
shared memory identifier. shm Ipid is the process ID of the last
process that performed a shmop(2) operation. shm nattch is
the number of processes that currently have this segment attached.
shm atime is the time of the last shmat operation,
shm=dtime is the time of the last shmdt operation, and
shm ctime is the time of the last shmctl(2) operation that
changed one of the members of the structure outlined earlier.
IPC PERMISSIONS
In the msgop(2) and msgctl(2) system-call descriptions, the
pennission required for an operation is interpreted as follows:
00400 Read by user.
00200 Write by user.
00060 Read/write by group.
00006 Read/write by others.
Message Operation Permissions
Read and write permissions on a msqid are granted to a process if
one or more of the following are true.
February, 1990
Revision C
The effective user ID of the process is the superuser.
The effective user ID of the process matches
msg perm. [c]uid in the data structure associated with
msqid, and the appropriate bit of the "user" portion (0600)
ofmsg_perm.modeisset
The effective user ID of the process does not match
msgyerm. [c]uid, the effective group ID of the process
matches msgyerm. [c]gid, and the appropriate bit of the
"group" portion (060) ofmsgyerm.mode is set.
The effective user ID of the process does not match
msgyerm. [c]uid, the effective group ID of the process
does not match msgyerm. [c]gid, and the appropriate bit
of the "other" portion (06) ofmsgyerm.mode is set
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