df plugin: Improve error message.

diff --git a/src/df.c b/src/df.c
index fc80ac3..2e9b2ae 100644 (file)
--- a/src/df.c
+++ b/src/df.c
@@ -33,12 +33,14 @@
 #  include <sys/statvfs.h>
 # endif
 # define STATANYFS statvfs
+# define STATANYFS_STR "statvfs"
 # define BLOCKSIZE(s) ((s).f_frsize ? (s).f_frsize : (s).f_bsize)
 #elif HAVE_STATFS
 # if HAVE_SYS_STATFS_H
 #  include <sys/statfs.h>
 # endif
 # define STATANYFS statfs
+# define STATANYFS_STR "statfs"
 # define BLOCKSIZE(s) (s).f_bsize
 #else
 # error "No applicable input method."
@@ -227,7 +229,8 @@ static int df_read (void)
                if (STATANYFS (mnt_ptr->dir, &statbuf) < 0)
                {
                        char errbuf[1024];
-                       ERROR ("statv?fs failed: %s",
+                       ERROR (STATANYFS_STR"(%s) failed: %s",
+                                       mnt_ptr->dir,
                                        sstrerror (errno, errbuf,
                                                sizeof (errbuf)));
                        continue;