Port file-system-info to non-Microsoft

* admin/merge-gnulib (GNULIB_MODULES): Add fsusage.
* doc/emacs/files.texi (Directories): Remove documentation of
now-obsolete directory-free-space-program and
directory-free-space-args.
* etc/NEWS: Mention change.
* etc/PROBLEMS: Slow df is no longer a problem.
* lib/fsusage.c, lib/fsusage.h, m4/fsusage.m4:
New files, copied from Gnulib.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.
* lisp/dired.el (dired-free-space-program)
(dired-free-space-args): These aliases are now obsolete.
* lisp/files.el (directory-free-space-program)
(directory-free-space-args): Now obsolete.
(get-free-disk-space): Just call file-system-info instead
of the now-obsolete directory-free-space-program.
* nt/gnulib-cfg.mk (OMIT_GNULIB_MODULE_fsusage): New macro.
* src/fileio.c: Include fsusage.h.
(blocks_to_bytes, Ffile_system_info) [!DOS_NT]: New functions.
(syms_of_fileio) [!DOS_NT]: Defsubr file-system-info.

1 files changed, 3 insertions, 7 deletions

diff --git a/etc/PROBLEMS b/etc/PROBLEMS
index 94c78b696db..2da99324b5f 100644
--- a/etc/PROBLEMS
+++ b/etc/PROBLEMS
@@ -557,7 +557,7 @@ and then choose /usr/bin/netkit-ftp.
 
 *** Dired is very slow.
 
-This could happen if invocation of the 'df' program takes a long
+This could happen if getting a file system's status takes a long
 time.  Possible reasons for this include:
 
   - ClearCase mounted filesystems (VOBs) that sometimes make 'df'
@@ -565,12 +565,8 @@ time.  Possible reasons for this include:
 
   - slow automounters on some old versions of Unix;
 
-  - slow operation of some versions of 'df'.
-
-To work around the problem, you could either (a) set the variable
-'directory-free-space-program' to nil, and thus prevent Emacs from
-invoking 'df'; (b) use 'df' from the GNU Coreutils package; or
-(c) use CVS, which is Free Software, instead of ClearCase.
+To work around the problem, you could use Git or some other
+free-software program, instead of ClearCase.
 
 *** ps-print commands fail to find prologue files ps-prin*.ps.