[linux-audio-dev] shared memory tools?

[rm]

On Thu, Mar 06, 2003 at 09:12:03PM +0200, Juhana Sadeharju wrote:
> Hello. I need two functions:
> 
> make_shm(int size, char *key)
>  -run by root
>  -creates a locked shared memory segment
>  -returns a key (preferably a string) which is used to
>   access the shared memory

shm segments are identified by key id (key_t), use ftok on a file to turn 
a string (the path to the file) into a key.


> Could somebody please write these routines to me? 

	yikes!  [ insert nasty comment here ]

> Or give good
> hints? 

_http://www.google.com
_http://www.acm.uiuc.edu/lug/presentations/shm/shm-5.html
_http://www.ecst.csuchico.edu/~beej/guide/ipc/shmem.html
_don't forget to free your shmem, it stays around after the process dies
	if you don't pay attention

> I have Jack and other codes, but it all is confusing
> when the shared memory should be accessed from separate process
> which is not fork() of the other.

pass the key id by socket, pipe, (dummy) file, etc. if it's a file you
can just pass the file path/name to the other program and it can use
ftok to generate the key.

	rob

----
Robert Melby
Georgia Institute of Technology, Atlanta Georgia, 30332
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