56 lines
979 B
C++
56 lines
979 B
C++
shm_client.c
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/*
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* shm-client - client program to demonstrate shared memory.
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*/
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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 <stdio.h>
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#define SHMSZ 27
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main()
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{
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int shmid;
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key_t key;
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char *shm, *s;
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/*
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* We need to get the segment named
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* "5678", created by the server.
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*/
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key = 5678;
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/*
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* Locate the segment.
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*/
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if ((shmid = shmget(key, SHMSZ, 0666)) < 0) {
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perror("shmget");
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exit(1);
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}
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/*
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* Now we attach the segment to our data space.
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*/
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if ((shm = shmat(shmid, NULL, 0)) == (char *) -1) {
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perror("shmat");
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exit(1);
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}
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/*
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* Now read what the server put in the memory.
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*/
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for (s = shm; *s != NULL; s++)
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putchar(*s);
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putchar('\n');
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/*
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* Finally, change the first character of the
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* segment to '*', indicating we have read
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* the segment.
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*/
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*shm = '*';
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exit(0);
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}
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