Description of problem:
 Our TPSs fail due to 'condrestart' of agent on physical machine is checking .pid file with '-f' (FILE exists and is a regular file) instead of '-s' (FILE exists and has a size greater than zero).
The .pid file is present even service is not able to run successfully. It's empty.
In case customer will install & try run agent on machine which doesn't posses virtio channel & then he will update agent - he ends with installation of 2 packages.
(eg: rhevm-guest-agent-1.0.7-8.el5 & rhevm-guest-agent-1.0.7-9.el5ev).


Version-Release number of selected component (if applicable):
rhevm-guest-agent-1.0.7-9.el5ev
rhevm-guest-agent-1.0.7-12.el6ev

How reproducible:
100%

Steps to Reproduce:
1. install agent, try to start daemon
2. yum update rhevm-guest-agent
3.

Actual results:
error: %postun(rhevm-guest-agent-1.0.7-8.el5.noarch) scriptlet failed, exit status 1

Expected results:


Additional info:


/etc/init.d/ovirt-guest-agent :
...
   condrestart)
        if [ -f ${pidfile} ] ; then


this leads to postuninstall issue:

error: %postun(rhevm-guest-agent-1.0.7-8.el5.noarch) scriptlet failed, exit status 1

because (RPM post-uninstall script):
...
if [ "$1" -ge 1 ]; then
    /sbin/service ovirt-guest-agent condrestart > /dev/null 2>&1