45 lines
780 B
C
45 lines
780 B
C
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// Adapted form IPC Message Queues slides
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// receiver.c
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// usage: ./receiver <key> <type>
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#include <stdio.h>
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#include <stdlib.h>
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#include <sys/types.h>
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#include <sys/ipc.h>
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#include <sys/shm.h>
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#include <string.h>
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struct text_message
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{
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long mtype;
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char mtext[100];
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};
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main(int argc, char *argv[])
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{
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int msid, v;
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struct text_message mess;
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/* Get a message handle */
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msid = msgget( (key_t) atoi ( argv[1] ), 0 );
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if ( msid == -1)
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{
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printf("Queue not joined\n");
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exit(1);
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}
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/* Read a message of the given type */
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v = msgrcv( msid, &mess, 100, atoi( argv[2] ), IPC_NOWAIT ); // Non-blocking
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if ( v < 0 )
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{
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printf("Error receiving message\n");
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exit(1);
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}
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else
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{
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printf("%d %s\n", mess.mtype, mess.mtext);
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msgctl( msid, IPC_RMID, 0);
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exit(0);
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}
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}
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