65 lines
933 B
C
65 lines
933 B
C
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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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#include <unistd.h>
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#include <string.h>
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#define SHMSZ 1024
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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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* "1234", created by the server.
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*/
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key = 1234;
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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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return 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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return 1;
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}
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/*
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* Zero out memory segment
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*/
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memset(shm,0,SHMSZ);
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s = shm;
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/*
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* Client writes user input character to memory
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* for server to read.
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*/
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for(;;){
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char tmp = getchar();
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// Eat the enter key
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getchar();
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if(tmp == 'q'){
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*shm = 'q';
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break;
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}
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*shm = tmp;
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}
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if(shmdt(shm) != 0)
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fprintf(stderr, "Could not close memory segment.\n");
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return 0;
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}
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