umount: add hint about lsof & fuser

This patch adds a hint about lsof and fuser to the "device is busy"
error message.

Addresses-Red-Hat-Bugzilla: #145844
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/mount/umount.c b/mount/umount.c
index 9690f2ac083fc8fa34c9b0bbaa7db905bfb2baa0..5b9398793fc740ebed85049fc06fc36c9efdfc46 100644 (file)
--- a/mount/umount.c
+++ b/mount/umount.c
@@ -152,7 +152,10 @@ static void complain(int err, const char *dev) {
     case EBUSY:
      /* Let us hope fstab has a line "proc /proc ..."
        and not "none /proc ..."*/
-      error (_("umount: %s: device is busy"), dev); break;
+      error (_("umount: %s: device is busy.\n"
+              "        (In some cases useful info about processes that use\n"
+              "         the device is found by lsof(8) or fuser(1))"), dev);
+      break;
     case ENOENT:
       error (_("umount: %s: not found"), dev); break;
     case EPERM: