[Libguestfs] [PATCH 2/4] daemon: Kill blkid cache to improve reliability of blkid commands.

[Richard W.M. Jones]

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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>From 21c42e9fabf6cea3d564e338a314479ef120502a Mon Sep 17 00:00:00 2001
From: Richard Jones <rjones at redhat.com>
Date: Tue, 1 Jun 2010 15:27:57 +0100
Subject: [PATCH 2/4] daemon: Kill blkid cache to improve reliability of blkid commands.

By killing the cache file, we make blkid work in situations such
as a just-created filesystem.
---
 daemon/blkid.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/daemon/blkid.c b/daemon/blkid.c
index 1ddc8cd..a619730 100644
--- a/daemon/blkid.c
+++ b/daemon/blkid.c
@@ -33,6 +33,13 @@ get_blkid_tag (const char *device, const char *tag)
   char *out, *err;
   int r;
 
+  /* Kill the cache file, forcing blkid to reread values from the
+   * original filesystems.  In blkid there is a '-p' option which is
+   * supposed to do this, but (a) it doesn't work and (b) that option
+   * is not supported in RHEL 5.
+   */
+  unlink ("/etc/blkid/blkid.tab");
+
   r = command (&out, &err,
                "blkid", "-o", "value", "-s", tag, device, NULL);
   if (r == -1) {
-- 
1.6.6.1