39 lines
758 B
C
39 lines
758 B
C
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/*
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* Test shmat(NULL).
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*
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* SPDX-License-Identifier: GPL-2.0-or-later
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*/
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#include <assert.h>
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#include <stdlib.h>
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#include <sys/ipc.h>
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#include <sys/shm.h>
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int main(void)
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{
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int shmid;
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char *p;
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int err;
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/* Create, attach and intialize shared memory. */
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shmid = shmget(IPC_PRIVATE, 1, IPC_CREAT | 0600);
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assert(shmid != -1);
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p = shmat(shmid, NULL, 0);
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assert(p != (void *)-1);
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*p = 42;
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/* Reattach, check that the value is still there. */
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err = shmdt(p);
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assert(err == 0);
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p = shmat(shmid, NULL, 0);
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assert(p != (void *)-1);
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assert(*p == 42);
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/* Detach. */
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err = shmdt(p);
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assert(err == 0);
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err = shmctl(shmid, IPC_RMID, NULL);
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assert(err == 0);
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return EXIT_SUCCESS;
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}
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