On 08/16/2011 01:35 PM, Eric Blake wrote:
On 08/16/2011 11:29 AM, Eric Blake wrote:
+++ b/src/util/virpidfile.c @@ -213,6 +213,8 @@ int virPidFileReadPathIfAlive(const char *path, #ifdef __linux__ if (virFileLinkPointsTo(procpath, binpath) == 0) *pid = -1; +#else + (void)binpath; #endif
Here, I'd rather mark binpath as ATTRIBUTE_UNUSED than add the #else preprocessor conditional. That is, ATTRIBUTE_UNUSED means only that the variable might be unused, not that it can't be used (so used on linux, unused otherwise qualifies).
Food for a separate patch: I see no reason why virFileLinkPointsTo won't work on cygwin. That is, the fact that we used #ifdef __linux__ is wrong, since cygwin also has a working /proc/pid/ file tree to determine if an executable is still valid; we should instead be doing #if PROCFS_AVAIL, along with some sort of configuration check that accepts both linux and cygwin procfs (or at least whatever aspect of procfs that we are relying on in this function).
I split this off and pushed the rest. If procfs's are different, then maybe we should use #if PROCFS_PID_EXE_LINK_AVAIL here. What is needed in this case seems to be that /proc/<pid>/exe is a symbolic link to the executable. This works in Linux and cygwin. Would testing via stat /proc/<pid>/exe | sed -n 's/.*\(symbolic link\).*/\1/p' be a valid test for this that works on all targeted platforms? Stefan