56 lines
960 B
C
56 lines
960 B
C
#include <fcntl.h>
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#include <stdio.h>
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#include <errno.h>
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#include <string.h>
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#include <stdlib.h>
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#include <unistd.h>
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int main(int argc, char **argv) {
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unsigned int c_flag = 0;
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unsigned int s_size = 0;
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int opt;
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while ((opt = getopt(argc, argv, "s:c")) != -1) {
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switch (opt) {
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case 's':
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s_size = atoi(optarg);
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break;
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case 'c':
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c_flag = 1;
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break;
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default:
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printf("truncate [file]\n\t[-c Do not create files] [-s=SIZE]\n");
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return 0;
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}
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}
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argv += optind;
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argc -= optind;
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if (argc == 0) {
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fprintf(stderr, "truncate: missing operand\n");
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return 1;
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}
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int flags = O_WRONLY | O_NONBLOCK;
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if (!c_flag)
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flags |= O_CREAT;
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int fd = open(argv[0], flags, 0666);
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if (fd < 0) {
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fprintf(stderr, "truncate %s %s\n", argv[0], strerror(errno));
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return 1;
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}
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if (ftruncate(fd, s_size) == -1) {
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close(fd);
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fprintf(stderr, "truncate %s %s\n", argv[0], strerror(errno));
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return 1;
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}
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close(fd);
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return 0;
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}
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