tests/zfs-tests/cmd/getversion.c

   1 /*
   2  * This file and its contents are supplied under the terms of the
   3  * Common Development and Distribution License ("CDDL"), version 1.0.
   4  * You may only use this file in accordance with the terms of version
   5  * 1.0 of the CDDL.
   6  *
   7  * A full copy of the text of the CDDL should have accompanied this
   8  * source.  A copy of the CDDL is also available via the Internet at
   9  * http://www.illumos.org/license/CDDL.
  10  */
  11
  12 /*
  13  * Copyright 2021 iXsystems, Inc.
  14  */
  15
  16 /*
  17  * FreeBSD and macOS expose file generation number through stat(2) and stat(1).
  18  * Linux exposes it instead through an ioctl.
  19  */
  20
  21 #include <sys/ioctl.h>
  22 #include <sys/fcntl.h>
  23 #include <linux/fs.h>
  24 #include <err.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <unistd.h>
  28
  29 int
  30 main(int argc, const char * const argv[])
  31 {
  32         if (argc != 2)
  33                 errx(EXIT_FAILURE, "usage: %s filename", argv[0]);
  34
  35         int fd = open(argv[1], O_RDONLY);
  36         if (fd == -1)
  37                 err(EXIT_FAILURE, "failed to open %s", argv[1]);
  38
  39         int gen = 0;
  40         if (ioctl(fd, FS_IOC_GETVERSION, &gen) == -1)
  41                 err(EXIT_FAILURE, "FS_IOC_GETVERSION failed");
  42
  43         (void) close(fd);
  44
  45         (void) printf("%d\n", gen);
  46
  47         return (EXIT_SUCCESS);
  48 }