39 lines
653 B
C
39 lines
653 B
C
#include <sys/types.h>
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#include <sys/wait.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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int
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main(int argc, char *argv[])
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{
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int fd, fd_parent;
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char buf[1];
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if (argc != 2) {
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return 1;
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}
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fd_parent = atoi(argv[1]);
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/* Writing to fd_parent should fail as it has to be closed at this
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* point */
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if (write(fd_parent, buf, sizeof(buf)) != -1) {
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return 2;
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}
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if (errno != EBADF) {
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return 3;
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}
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/* If we open a new file, the fd we obtain should be identical to
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* fd_parent */
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fd = open("open_identical_fd", O_CREAT|O_RDWR, 0660);
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if (fd != fd_parent) {
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return 4;
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}
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return 0;
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}
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