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

INTR0 (2) INTR0 (2)
The process's effective user ID is super-user.
The process's effective user ID matches the user ID of the
owner of the file and the appropriate access bit of the
"owner" portion (0700) of the file mode is set.
The process's effective user ID does not match the user ID
of the owner of the file, and the process's effective group
ID matches the group of the file and the appropriate
access bit of the "group" portion (070) of the file mode is
set.
The process's effective user ID does not match the user ID
of the owner of the file, and the process's effective group
ID does not match the group ID of the file, and the
appropriate access bit of the "other" portion (07) of the
file mode is set.
Otherwise, the corresponding permissions are denied.
Message Queue Identifier
A message queue identifier (msqid) is a unique positive integer
created by a msgget(2) system call. Each msqid has a message
queue and a data structure associated with it. The data structure
is referred to as msqid_ds and contains the following members:
struct
ushort
ushort
ushort
ushort
time_t
time_t
time_t
ipc_perm msg_perm;
msg_qnum;
msg_qbytes;
msg_lspid;
msg_lrpid;
msg_stime;
msg_rtime;
msg_ctime;
I* operation permission struct *I
I* number of msgs on q *I
I* max number of bytes on q *I
I* pid of last msgsnd operation *I
I* pid of last msgrcv operation *I
I* last msgsnd time *I
I* last msgrcv time *I
I* last change time *I
I* Times measured in sees since *I
I* 00:00:00 GMT, Jan. 1, 1970 *I
Msg_perm is a ipc_perm structure that specifies the message
operation permission (see below). This structure includes the fol­
lowing members:
ushort
ushort
ushort
ushort
ushort
cuid;
cgid;
uid;
gid;
mode;
I* creator user i d *I
I* creator group id *I
I* user id *I
I* group id *I
I* r lw permission *I
Msg_qnum is the number of messages currently on the queue.
Msg_qbytes is the maximum number of bytes allowed on the
queue. Msg_lspid is the process id of the last process that per-
formed a msgsnd operation. Msg_lrpid is the process id of the
last process that performed a msgrcv operation. Msg_stime is
the time of the last msgsnd operation, msg_rtime is the time of
the last msgrcv operation, and msg_ctime is the time of the last
msgctl(2) operation that changed a member of the above structure.
Message Operation Permissions.
In the msgop(2) and msgctl(2) system call descriptions, the
- 6-
-�