* src/fileio.c (file_name_case_insensitive_p) [DARWIN_OS]: Fix
mistakes in recent commit.

* src/fileio.c (file_name_case_insensitive_p): Try skipping the
Darwin code and instead using pathconf with _PC_CASE_SENSITIVE.
Leave in two alternatives conditionally compiled based on
DARWIN_OS_CASE_SENSITIVE_FIXME in case pathconf doesn't work.

* etc/PROBLEMS: Mention the possible problem with pathconf on
Mac OS X.

This reverts commit 2f5e0b1bf7b0ac4f450847db34d599a072020600.
I see no reason for removing code, documentation, and comments
in the original commit.

* doc/lispref/files.texi (Truenames): Simplify documentation,
to avoid giving too much platform-specific information that
may not be accurate anyway.
* src/fileio.c (file_name_case_insensitive_p): Use pathconf with
_PC_CASE_SENSITIVE if _PC_CASE_INSENSITIVE is not available.
Otherwise if one approach fails (e.g., with errno == EINVAL), fall
back on an alternative rather than returning false.  Try skipping
the Darwin code, as it (1) no longer seems to be needed and (2)
does not seem to match the Apple documentation.  Leave in two
alternatives conditionally compiled based on
DARWIN_OS_CASE_SENSITIVE_FIXME in case (1) or (2) is incorrect.

* src/fileio.c (file_name_case_insensitive_p)
(Ffile_name_case_insensitive_p):  New functions.
(Frename_file): Allow renames that simply change case when the
FILE argument is on a case-insensitive filesystem.  (Bug#24441)

* lisp/dired-aux.el (dired-do-create-files): Use
'file-name-case-insensitive-p' instead of 'system-type' to check
for case-insensitivity.  (Bug#24441)

* doc/lispref/files.texi (Truenames): Document
'file-name-case-insensitive-p'.

* etc/NEWS: Indicate the removed variables.
* lisp/emacs-lisp/edebug.el (edebug-outside-mark): Fix comment.
* lisp/subr.el (default-mode-line-format, default-header-line-format):
(default-line-spacing, default-abbrev-mode, default-ctl-arrow):
(default-truncate-lines, default-left-margin, default-tab-width):
(default-case-fold-search, default-left-margin-width):
(default-right-margin-width, default-left-fringe-width):
(default-right-fringe-width, default-fringes-outside-margins):
(default-scroll-bar-width, default-vertical-scroll-bar):
(default-indicate-empty-lines, default-indicate-buffer-boundaries):
(default-fringe-indicator-alist, default-fringe-cursor-alist):
(default-scroll-up-aggressively, default-scroll-down-aggressively):
(default-fill-column, default-cursor-type):
(default-cursor-in-non-selected-windows):
(default-buffer-file-coding-system, default-major-mode):
(default-enable-multibyte-characters): Remove obsolete declarations.
* src/buffer.c (default-mode-line-format, default-header-line-format):
(default-line-spacing, default-abbrev-mode, default-ctl-arrow):
(default-truncate-lines, default-left-margin, default-tab-width):
(default-case-fold-search, default-left-margin-width):
(default-right-margin-width, default-left-fringe-width):
(default-right-fringe-width, default-fringes-outside-margins):
(default-scroll-bar-width, default-vertical-scroll-bar):
(default-indicate-empty-lines, default-indicate-buffer-boundaries):
(default-fringe-indicator-alist, default-fringe-cursor-alist):
(default-scroll-up-aggressively, default-scroll-down-aggressively):
(default-fill-column, default-cursor-type):
(default-cursor-in-non-selected-windows):
(default-buffer-file-coding-system, default-major-mode):
(default-enable-multibyte-characters): Remove.
* src/fileio.c (choose_write_coding_system): Fix comment.
* src/lisp.h (DEFVAR_BUFFER_DEFAULTS): Remove.

This fixes a recently-introduced bug in delete-directory,
where the code assumes the C locale when determining
whether a file-error corresponds to a missing file (Bug#24714).
* doc/lispref/errors.texi (Standard Errors):
* doc/lispref/files.texi (Changing Files):
* etc/NEWS:
Document this.
* doc/lispref/loading.texi (How Programs Do Loading):
Say "a file-error" rather than "the error file-error" since
it might be a file-missing now.
* lisp/emacs-lisp/bytecomp.el (byte-compile-file):
* lisp/epa-file.el (epa-file--find-file-not-found-function):
(epa-file-insert-file-contents, epa-file-write-region):
* lisp/ffap.el (find-file-at-point, dired-at-point):
* lisp/jka-compr.el (jka-compr-insert-file-contents)
(jka-compr-insert-file-contents):
* lisp/net/ange-ftp.el (ange-ftp-barf-if-not-directory)
(ange-ftp-insert-file-contents, ange-ftp-copy-file-internal):
* lisp/progmodes/etags.el (visit-tags-table):
* lisp/url/url-handlers.el (url-copy-file):
* src/fileio.c (report_file_errno):
Signal file-missing if appropriate.
* lisp/epa-file.el (epa-file-insert-file-contents):
* lisp/jka-compr.el (jka-compr-insert-file-contents):
Don't assume file-error is a leaf in the error hierarchy.
* lisp/files.el (files--force):
* lisp/gnus/nnmaildir.el (nnmaildir--enoent-p):
* lisp/jka-compr.el (jka-compr-insert-file-contents):
Use file-missing to detect whether the file is missing.
* lisp/url/url-handlers.el (url-copy-file):
Signal file-already-exists if appropriate.
* src/fileio.c (syms_of_fileio): Define file-missing.

2016-10-18  Paul Eggert  <eggert@cs.ucla.edu>

* src/w32.c (_ANONYMOUS_UNION, _ANONYMOUS_STRUCT): Remove
definitions of these macros, which seem to be unneeded and cause
compiler warnings.
* src/fileio.c (NOMINMAX): Avoid compiler warnings about unused
macros.
* src/firstfile.c (dummy_main_reference): Rename from 'dummy' and
make it external, to avoid compiler warning.

* src/fileio.c (Finsert_file_contents): Run before-change-hooks before
deleting the old buffer content.
* src/lisp.h (del_range_byte):
* src/insdel.c (del_range_byte): Drop the last argument.
* src/fns.c (Fbase64_encode_region): Adjust accordingly.