xen: Don't emit warning message if /proc/xen/capabilities file does not exist.

On Amazon EC2:

xen
grep: /proc/xen/capabilities: No such file or directory
xen-domU

The warning is harmless but should not be printed.

Thanks: Can Zhang for testing.
(cherry picked from commit 8709c0e87dc3124b1a64d85654d6d4904702d767)

diff --git a/virt-what.in b/virt-what.in
index bf663aa..4b6d3b8 100644 (file)
--- a/virt-what.in
+++ b/virt-what.in
@@ -199,7 +199,7 @@ if [ "$cpuid" = "XenVMMXenVMM" ]; then
     skip_qemu_kvm=true
 elif [ -d "${root}/proc/xen" ]; then
     echo xen
-    if grep -q "control_d" "${root}/proc/xen/capabilities"; then
+    if grep -q "control_d" "${root}/proc/xen/capabilities" 2>/dev/null; then
         echo xen-dom0
     else
         echo xen-domU