* files.el (get-free-disk-space): Search more robustly for "available" column.

Suggested by Ehud Karni <ehud@unix.mvs.co.il>:
http://lists.gnu.org/archive/html/emacs-devel/2010-09/msg00163.html

2 files changed, 29 insertions, 18 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 69626e2e455..026b05a7231 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2010-09-05  Chong Yidong  <cyd@stupidchicken.com>
+
+        * files.el (get-free-disk-space): Search more robustly for
+        "available" column.  Suggested by Ehud Karni
+        <ehud@unix.mvs.co.il>.
+
 2010-09-05  Juanma Barranquero  <lekktu@gmail.com>
 
         * international/uni-bidi.el:
diff --git a/lisp/files.el b/lisp/files.el
index 73a0c5c9e24..41bd9bd9c25 100644
--- a/lisp/files.el
+++ b/lisp/files.el
@@ -5563,12 +5563,14 @@ preference to the program given by this variable."
 
 (defun get-free-disk-space (dir)
   "Return the amount of free space on directory DIR's file system.
-The result is a string that gives the number of free 1KB blocks,
-or nil if the system call or the program which retrieve the information
-fail.  It returns also nil when DIR is a remote directory.
-
-This function calls `file-system-info' if it is available, or invokes the
-program specified by `directory-free-space-program' if that is non-nil."
+The return value is a string describing the amount of free
+space (normally, the number of free 1KB blocks).
+
+This function calls `file-system-info' if it is available, or
+invokes the program specified by `directory-free-space-program'
+and `directory-free-space-args'.  If the system call or program
+is unsuccessful, or if DIR is a remote directory, this function
+returns nil."
   (unless (file-remote-p dir)
     ;; Try to find the number of free blocks.  Non-Posix systems don't
     ;; always have df, but might have an equivalent system call.
@@ -5588,19 +5590,22 @@ program specified by `directory-free-space-program' if that is non-nil."
                                          directory-free-space-args
                                          dir)
                            0)))
-            ;; Usual format is a header line followed by a line of
-            ;; numbers.
+            ;; Usual format is as follows:
+            ;; Filesystem ...    Used  Available  Capacity ...
+            ;; /dev/sda6  ...48106535   35481255  10669850 ...
             (goto-char (point-min))
-            (forward-line 1)
-            (if (not (eobp))
-                (progn
-                  ;; Move to the end of the "available blocks" number.
-                  (skip-chars-forward "^ \t")
-                  (forward-word 3)
-                  ;; Copy it into AVAILABLE.
-                  (let ((end (point)))
-                    (forward-word -1)
-                    (buffer-substring (point) end))))))))))
+            (when (re-search-forward " +Avail[^ \n]*"
+                                     (line-end-position) t)
+              (let ((beg (match-beginning 0))
+                    (end (match-end 0))
+                    str)
+                (forward-line 1)
+                (setq str
+                      (buffer-substring-no-properties
+                       (+ beg (point) (- (point-min)))
+                       (+ end (point) (- (point-min)))))
+                (when (string-match "\\` *\\([^ ]+\\)" str)
+                  (match-string 1 str))))))))))
 
 ;; The following expression replaces `dired-move-to-filename-regexp'.
 (defvar directory-listing-before-filename-regexp