morpheus-base

morpheus base system
git clone git://git.2f30.org/morpheus-base.git
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truncate.c (895B)


      1 /* See LICENSE file for copyright and license details. */
      2 #include <sys/stat.h>
      3 
      4 #include <fcntl.h>
      5 #include <stdio.h>
      6 #include <stdlib.h>
      7 #include <unistd.h>
      8 
      9 #include "util.h"
     10 
     11 static void
     12 usage(void)
     13 {
     14 	eprintf("usage: %s [-c] -s size file...\n", argv0);
     15 }
     16 
     17 int
     18 main(int argc, char *argv[])
     19 {
     20 	int cflag = 0, sflag = 0;
     21 	int fd, i, ret = 0;
     22 	long size = 0;
     23 
     24 	ARGBEGIN {
     25 	case 's':
     26 		sflag = 1;
     27 		size = estrtol(EARGF(usage()), 10);
     28 		break;
     29 	case 'c':
     30 		cflag = 1;
     31 		break;
     32 	default:
     33 		usage();
     34 	} ARGEND;
     35 
     36 	if (argc < 1 || sflag == 0)
     37 		usage();
     38 
     39 	for (i = 0; i < argc; i++) {
     40 		fd = open(argv[i], O_WRONLY | (cflag ? 0 : O_CREAT), 0644);
     41 		if (fd < 0) {
     42 			weprintf("open: cannot open `%s' for writing:", argv[i]);
     43 			ret = 1;
     44 			continue;
     45 		}
     46 		if (ftruncate(fd, size) < 0) {
     47 			weprintf("ftruncate: cannot open `%s' for writing:", argv[i]);
     48 			ret = 1;
     49 		}
     50 		close(fd);
     51 	}
     52 	return ret;
     53 }