Revert too-picky file-access tests

Problem reported by Andreas Schwab (Bug#37475).
* doc/lispref/files.texi (Writing to Files)
(Testing Accessibility, Kinds of Files):
Document that accessibility and file-type predicates return nil
if there is trouble determining accessibility or type.
* etc/NEWS: Adjust, and list the affected primitives.
* src/callproc.c (init_callproc): Go back to Ffile_exists_p.
* src/fileio.c (PICKY_EACCES, file_test_errno):
Remove.  All uses removed.
(Ffile_name_case_insensitive_p, Ffile_exists_p, Ffile_symlink_p)
(Ffile_directory_p, Ffile_regular_p): Document that these
functions return nil if there is trouble.
(Ffile_name_case_insensitive_p, check_file_access)
(Ffile_writable_p, Ffile_symlink_p, Ffile_directory_p)
(Ffile_accessible_directory_p, Ffile_regular_p)
* src/lread.c (Fload):
Go back to treating trouble in determining the answer as if the
file were missing.
* src/fileio.c (Ffile_newer_than_file_p): Use file_attribute_errno
not file_test_errno, since returning nil is not appropriate when
there are two files to test; e.g., in the rare cases where both
file timestamps have overflowed then neither t nor nil is correct.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/callproc.c b/src/callproc.c
index dbbf15c792a..007465cd405 100644
--- a/src/callproc.c
+++ b/src/callproc.c
@@ -1567,12 +1567,12 @@ init_callproc (void)
 
       tem = Fexpand_file_name (build_string ("NEWS"), Vdata_directory);
       if (!NILP (Fequal (srcdir, Vinvocation_directory))
-	  || !file_access_p (SSDATA (tem), F_OK))
+	  || NILP (Ffile_exists_p (tem)))
 	{
 	  Lisp_Object newdir;
 	  newdir = Fexpand_file_name (build_string ("../etc/"), lispdir);
 	  tem = Fexpand_file_name (build_string ("NEWS"), newdir);
-	  if (file_access_p (SSDATA (tem), F_OK))
+	  if (!NILP (Ffile_exists_p (tem)))
 	    Vdata_directory = newdir;
 	}
     }