08-25-2008
Print out errno too to why it doesn't work.
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mesg(5) File Formats Manual mesg(5)
NAME
mesg - enable or disable System V IPC messages at boot time (OBSOLETE)
DESCRIPTION
The tunable is obsolete.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 allocated 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 referenced 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 parameter values. After installation,
some tunable parameters may no longer be at the default or recommended values. For information about the effects of installation on tun-
able values, consult the documentation for the kernel software being installed. For information about optional kernel software that was
factory installed on your system, see at
AUTHOR
was developed by AT&T.
SEE ALSO
ipcrm(1), ipcs(1), msgctl(2), msgget(2), msgrcv(2), msgsnd(2), msgmnb(5), msgmni(5), msgmbs(5), msgtql(5).
OBSOLETE
Tunable Kernel Parameters mesg(5)