Implement the '-F' option for mount & umount which allows the user to

specify an alternate fstab file.

2 files changed, 17 insertions, 2 deletions

diff --git a/sbin/mount/mount.8 b/sbin/mount/mount.8
index b1ae841..741904b 100644
--- a/sbin/mount/mount.8
+++ b/sbin/mount/mount.8
@@ -41,6 +41,7 @@
 .Sh SYNOPSIS
 .Nm
 .Op Fl adfpruvw
+.Op Fl F Ar fstab
 .Op Fl t Ar ufs | external_type
 .Nm
 .Op Fl dfpruvw
@@ -93,6 +94,10 @@ flag to
 determine what the
 .Nm
 command is trying to do.
+.It Fl F Ar fstab
+Specify the
+.Pa fstab
+file to use.
 .It Fl f
 Forces the revocation of write access when trying to downgrade
 a file system mount status from read-write to read-only.
@@ -406,6 +411,13 @@ Note that
 support for a particular file system might be provided either on a static
 (kernel compile-time), or dynamic basis (loaded as a kernel module by
 .Xr kldload 8 ) .
+.Sh ENVIRONMENT
+.Bl -tag -width PATH_FSTAB
+.It Pa PATH_FSTAB
+If the environment variable
+.Pa PATH_FSTAB
+is set all operations are performed against the specified file.
+.El
 .Sh FILES
 .Bl -tag -width /etc/fstab -compact
 .It Pa /etc/fstab
diff --git a/sbin/mount/mount.c b/sbin/mount/mount.c
index f0daa55..4fccd91 100644
--- a/sbin/mount/mount.c
+++ b/sbin/mount/mount.c
@@ -140,7 +140,7 @@ main(argc, argv)
 	options = NULL;
 	vfslist = NULL;
 	vfstype = "ufs";
-	while ((ch = getopt(argc, argv, "adfo:prwt:uv")) != -1)
+	while ((ch = getopt(argc, argv, "adF:fo:prwt:uv")) != -1)
 		switch (ch) {
 		case 'a':
 			all = 1;
@@ -148,6 +148,9 @@ main(argc, argv)
 		case 'd':
 			debug = 1;
 			break;
+		case 'F':
+			setfstab(optarg);
+			break;
 		case 'f':
 			init_flags |= MNT_FORCE;
 			break;
@@ -712,7 +715,7 @@ usage()
 
 	(void)fprintf(stderr, "%s\n%s\n%s\n",
 "usage: mount [-dfpruvw] [-o options] [-t ufs | external_type] special node",
-"       mount [-adfpruvw] [-t ufs | external_type]",
+"       mount [-adfpruvw] [ -F fstab] [-t ufs | external_type]",
 "       mount [-dfpruvw] special | node");
 	exit(1);
 }