Include stddef.h.

Include stddef.h.
(getwd): Delete macro.
(startup_dir): New variable.
(getwd): Return directory in which Emacs started.
(init_user_info): Set SHELL environment variable if not set.
(parse_root, get_long_basename, w32_get_long_filename): New functions.
(init_environment): Look for CMDPROXY.
Make sure that PATH and COMSPEC are capitalized in the environment.
Record startup directory.
(get_emacs_configuration, sys_rename): Use OS_WIN95.
(map_w32_filename): Calculate returned string correctly.

(sys_fopen): Use _fdopen.
(sys_link): Support NTFS links.
(sys_rename): Use a long file name for temporary name.
(sys_pipe): Make pipes binary and non-inheritable.
(sys_read, sys_write): Spoof text mode translation for pipes
and sockets.

(hashval): Simplify.
(generate_inode_val): Use long file name version of file.

(stat): Optimize by using active readdir info.
Set fake_inode to 0 for directories.
Set fake_inode to xor of file indexes for files.
Don't use generate_inode_val to set inode value.

(volume_info_data): Renamed from volume_info.
(volume_info, fixed_drives, volume_cache): New variables.
(DRIVE_INDEX, VOLINFO_STILL_VALID): New macros.
(lookup_volume_info, add_volume_info, GetCachedVolumeInformation):
New functions.
(get_volume_info): Use volume_info_data.
Use GetCachedVolumeInformation.

(init_ntproc): No longer restrict to one DOS subprocess.
Use CRT _open and _fdopen.
Cache fixed drive information.