Fix file-attributes race on GNU hosts

* doc/lispref/files.texi (File Attributes):
Document file-attributes atomicity.
* etc/NEWS: Document the fix.
* src/dired.c (file_attributes): New args DIRNAME and FILENAME,
for diagnostics.  All callers changed.  On platforms like
GNU/Linux that support O_PATH, fix a race condition in
file-attributes and similar functions, so that these functions do
not return nonsense if a directory entry is replaced while getting
its attributes.  On non-GNU platforms, do a better (though not
perfect) job of detecting the race, and return nil if detected.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/sysdep.c b/src/sysdep.c
index 12e9c83ee90..b66a7453172 100644
--- a/src/sysdep.c
+++ b/src/sysdep.c
@@ -2930,7 +2930,7 @@ list_system_processes (void)
      process.  */
   procdir = build_string ("/proc");
   match = build_string ("[0-9]+");
-  proclist = directory_files_internal (procdir, Qnil, match, Qt, 0, Qnil);
+  proclist = directory_files_internal (procdir, Qnil, match, Qt, false, Qnil);
 
   /* `proclist' gives process IDs as strings.  Destructively convert
      each string into a number.  */