clear errno after successful call

When preparing the debian stable backport, I am seeing a call to statvfs()
succeed, but also set errno to 2 (ENOENT). Not sure why this happens;
I am in a schroot when it does happen, or perhaps stable's libc is a little
broken and sets errno incorrectly. Anyway, it should be perfectly fine to
clear errno after the successful call, rather than before it.

1 files changed, 3 insertions, 2 deletions

diff --git a/Utility/libdiskfree.c b/Utility/libdiskfree.c
index b68abd0c4..54e8c0894 100644
--- a/Utility/libdiskfree.c
+++ b/Utility/libdiskfree.c
@@ -58,9 +58,10 @@ unsigned long long int diskfree(const char *path) {
 	unsigned long long int available, blocksize;
 	struct STATSTRUCT buf;
 
-	errno = 0;
-	if (STATCALL(path, &buf) != 0)
+	if (STATCALL(path, &buf) != 0) {
 		return 0; /* errno is set */
+	}
+	errno = 0;
 
 	available = buf.f_bavail;
 	blocksize = buf.f_bsize;