mesg.5 (2010 09)

m
mesg(5) OBSOLETE mesg(5)
(Tunable Kernel Parameters)
NAME
mesg - enable or disable System V IPC messages at boot time (OBSOLETE)
DESCRIPTION
The
mesg tunable is obsolete. The System V IPC message subsystem is always enabled.
Overview
A System V message is just a sequence of bytes that can be passed between cooperating processes via a
message queue. Messages can be of any length up to a tunable maximum. Messages larger than 64 bytes
(not tunable) are stored in reserved kernel memory. Messages equal to or smaller than 64 bytes are allo-
cated with the message header and therefore do not consume extra kernel structure to maintain the
memory. Each message is "typed" with an application-specific number. Each message queue is refer-
enced by a unique ID, and can contain multiple individual messages.
The process receiving a message can get the "first" message (FIFO), the first of a specified type, the first of
a group of types, or wait for a specific type to appear.
WARNINGS
Installation of optional kernel software, from HP or other vendors, may cause changes to tunable parame-
ter values. After installation, some tunable parameters may no longer be at the default or recommended
values. For information about the effects of installation on tunable values, consult the documentation for
the kernel software being installed. For information about optional kernel software that was factory
installed on your system, see HP-UX Release Notes at
http://www.hp.com/go/hpux-core-docs
.
AUTHOR
mesg was developed by AT&T.
SEE ALSO
ipcrm(1), ipcs(1), kctune(1M), msgctl(2), msgget(2), msgrcv(2), msgsnd(2), msgmnb(5), msgmni(5),
msgmbs(5), msgtql(5).
HP-UX 11i Version 3: September 2010 − 1 − Hewlett-Packard Company 1