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MSP, Sockets and Queues

MSP uses a single STREAM socket (path) in the INET domain to communicate between any two tasks and a STREAM socket pair in the UNIX domain to send/receive local (internal) messages. Messages on the sockets specify a `queue' in the receiving task for which they are intended and a queue in the sending task to which replies should be sent.

The MSP message reading function accepts a list of `receive' queues on which it should look for messages and the MSP message sending function accepts a `send' queue which specifies a socket and a receive queue in the other task. N.B. the reply queue may be given as MSP__NULL_SENDQ (it is a send queue in the task which has to reply).

AMS uses separate MSP queues within each task for:

The AMS user will not need to know about MSP queues.



next up previous 199
Next: Communications Directory
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AMS The Unix ADAM Message System
Starlink User Note 241
B D Kelly (ROE)
A J Chipperfield (RAL)
16 August 2001
E-mail:ussc@star.rl.ac.uk

Copyright © 2000 Council for the Central Laboratory of the Research Councils