src/tests/system/libroot/posix/truncate.cpp

   1 /*
   2  * Copyright 2008, Axel Dörfler, axeld@pinc-software.de.
   3  * Distributed under the terms of the MIT License.
   4  */
   5
   6
   7 #include <ctype.h>
   8 #include <errno.h>
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12 #include <sys/stat.h>
  13 #include <unistd.h>
  14
  15
  16 extern const char *__progname;
  17
  18
  19 int
  20 main(int argc, char **argv)
  21 {
  22         if (argc < 3) {
  23                 fprintf(stderr, "usage: %s <file> <size>\n", __progname);
  24                 return 1;
  25         }
  26
  27         struct stat st;
  28         if (stat(argv[1], &st) != 0) {
  29                 fprintf(stderr, "%s: cannot stat file \"%s\": %s\n", __progname,
  30                         argv[1], strerror(errno));
  31                 return 1;
  32         }
  33
  34         off_t newSize = strtoll(argv[2], NULL, 0);
  35
  36         printf("size   %10Ld\n", st.st_size);
  37         printf("wanted %10Ld\n", newSize);
  38         printf("Do you really want to truncate the file [y/N]? ");
  39         fflush(stdout);
  40
  41         char yes[10];
  42         if (fgets(yes, sizeof(yes), stdin) == NULL || tolower(yes[0]) != 'y')
  43                 return 0;
  44
  45         if (truncate(argv[1], newSize) != 0) {
  46                 fprintf(stderr, "%s: cannot truncate file \"%s\": %s\n", __progname,
  47                         argv[1], strerror(errno));
  48                 return 1;
  49         }
  50
  51         return 0;
  52 }