HP-UX Reference (11i v3 07/02) - 7 Device (Special) Files, 9 General Information, Index (vol 10)

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glossary(9) glossary(9)
pid_t msg_lrpid; /* pid of last msgrcv operation */
time_t msg_stime; /* last msgsnd time */
time_t msg_rtime; /* last msgrcv time */
time_t msg_ctime; /* last change time */
/* Times measured in secs since */
/* 00:00:00 GMT, Jan. 1, 1970 */
Message queue identifiers can be created using ftok(3C).
msg_perm is a ipc_perm structure that specifies the message operation permission (see below). This
structure includes the following members:
uid_t cuid; /* creator user id */
gid_t cgid; /* creator group id */
uid_t uid; /* user id */
gid_t gid; /* group id */
mode_t mode; /* r/w permission */
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 performed 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 permission required for an operation is indi-
cated for each operation. Whether a particular process has these permissions for an object is determined by
the object’s permission mode bits as follows:
00400 Read by user
00200 Write by user
00060 Read, Write by group
00006 Read, Write by others
Read and Write permissions on a msqid are granted to a process if one or more of the following are true:
• The process’s effective user ID is superuser.
• The process’s effective user ID matches
msg_perm.[c]uid in the data structure associated with
msqid and the appropriate bit of the "user" portion (0600) of
msg_perm.mode is set.
• The process’s effective user ID does not match
msg_perm.[c]uid and either the process’s effective
group ID matches
msg_perm.[c]gid or one of msg_perm.[c]gid is in the process’s group access
list and the appropriate bit of the "group" portion (00060) of
msg_perm.mode is set.
• The process’s effective user ID does not match
msg_perm.[c]uid and the process’s effective group
ID does not match
msg_perm.[c]gid and neither of msg_perm.[c]gid
is in the process’s group
access list and the appropriate bit of the "other" portion (06) of
msg_perm.mode is set.
Otherwise, the corresponding permissions are denied.
metacharacter
A character that has special meaning to the HP-UX shell, as well as to commands such as
ed, find, and
grep (see ed(1), find(1), and grep(1)). The set of metacharacters includes: !, ", &,
’, *, ;, <, >, ?, [, ],
‘
, and |. Refer to sh(1) and the related shell manual entries for the meaning associated with each. See
also regular expression.
minor number
A number that is an attribute of special files, specified during their creation and used whenever they are
accessed, to enable I/O to or from specific devices. This number is passed to the device driver and is used to
select which device in a family of devices is to be used, and possibly some operational modes. The exact for-
mat and meaning of the minor number depends both on the driver and on the addressing format (legacy
or agile) being used. In legacy format, the minor number encodes path information, but in agile format, the
minor number is opaque and based on the WWID.
258 Hewlett-Packard Company − 13 − HP-UX 11i Version 3: February 2007