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Top Forums Programming message queues and multi-process Post 302133156 by rvan on Wednesday 22nd of August 2007 07:26:47 AM
Old 08-22-2007
Quote:
Originally Posted by rvan
Hi,

Am supposed to use message queues to send and receive messages between the processes. when i was working on that i realised that the message qid and the message queue related data should be maintained in a shared memory so that it can be accessed by all the processes. Could anybody refer some link which helps me out in this...


P.S. i have gone through Richard Stevens IPC volume 2 but i couldn't exactly find such a scenario..Stevens more on memory mapped I/O..


Thanks,
Am using Posix message queues
 

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nullmailer-queue(8)					      System Manager's Manual					       nullmailer-queue(8)

NAME
nullmailer-queue - insert mail messages into the queue SYNOPSIS
nullmailer-queue DESCRIPTION
This program reads a formatted mail message from standard input and safely injects it into the outgoing mail queue. The data sent into standard input is expected to have the following format: one line containing the envelope sender, one or more lines con- taining the recipients, a single blank line, and then the contents of the message exactly as it is to be transmitted to the destination. All lines are terminated with a single line-feed character. All addresses must contain a fully-qualified domain name. RETURN VALUE
Exits 0 if it successfully queues the message. If it failed to queue the message, it exits 1 and prints an error message to stdandard out- put. CONTROL FILES
adminaddr If this file is not empty, all recipients to users at either "localhost" (the literal string) or the canonical host name (from /etc/mailname) are remapped to this address. This is provided to allow local daemons to be able to send email to "somebody@local- host" and have it go somewhere sensible instead of being bounced by your relay host. OTHER FILES
/var/spool/nullmailer/queue The directory into which the completed messages are moved. /var/spool/nullmailer/tmp The directory in which messages are formed temporarily. /var/spool/nullmailer/trigger A pipe used to trigger nullmailer-send to immediately start sending the message from the queue. SEE ALSO
nullmailer-inject(1), nullmailer-send(8) LIMITATIONS
This program should enforce system-wide configurable message length limits. nullmailer-queue(8)
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