diff --git a/src/os/darwin/darwin_sigar.c b/src/os/darwin/darwin_sigar.c
index 03d69d74..a18b03cf 100644
--- a/src/os/darwin/darwin_sigar.c
+++ b/src/os/darwin/darwin_sigar.c
@@ -1307,7 +1307,7 @@ int sigar_file_system_usage_get(sigar_t *sigar,
     fsusage->avail = SIGAR_FS_BLOCKS_TO_BYTES(buf, f_bavail);
     fsusage->used  = fsusage->total - fsusage->free;
     fsusage->files = buf.f_files;
-    fsusage->free_files = buf.f_files;
+    fsusage->free_files = buf.f_ffree;
     fsusage->use_percent = sigar_file_system_usage_calc_used(sigar, fsusage);
 
 #ifdef DARWIN