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Message Queue Problem Again..

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# 1  
Old 07-05-2005
Message Queue Problem Again..
Is there any way one can delete , say , a particular message from a message queue on system V?
# 2  
Old 07-05-2005
Reading a message from the message queue using msgrcv essentially removes the message from the queue.

To quote the msgrcv man page:
Quote:
The system call msgrcv reads a message from the message queue specified by msqid into the msgbuf pointed to by the msgp argument removing from the queue, on success, the read message.
Check this link.
Last edited by blowtorch; 07-05-2005 at 03:24 AM.. Reason: To add a link to the man page
# 3  
Old 07-05-2005
Just to elaborate on Blow Torch's answer. The message queues are internal kernel structures and cannot be viewed or changed directly by your process.

On some implementations you can get the memory address of the first and last message in a queue, but because this is outside your programs alloted memory area, the OS will never let you access the address directly with a pointer.

The only way your process can get at the contents on the message queue is to use the defined interface - msgrecv().
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