Callers changed.
(message1, message1_nolog): String must be ASCII-only.
(message2, message2_nolog): Now static.
(x_consider_frame_title): Use size_byte.
(display_text_line): Likewise.
And scan Voverlay_arrow_string by bytes and chars.
(display_menu_bar): Call display_string with a byte size.
(display_mode_line): Call display_string with a byte size.
(describe_vector): Pass new args to insert_from_string.
(Ftext_char_description): Use make_multibyte_string.
(Fkey_binding): Scan PREFIX a char at a time.
(Fkey_description): Scan KEYS by chars.
(Fexecute_extended_command): Likewise.
(read_char_minibuf_menu_prompt): Use message2_nolog, not message1.
(parse_modifiers): Use size_byte.
(echo_char): Use size_byte.
(parse_modifiers_uncached): Likewise.
(record_char): Likewise.
(parse_solitary_modifier): Likewise.
(read_char): Use Faref on Vkeyboard_translate_table
if it is a string.
(apply_modifiers_uncached): New arg base_len_byte. Calls changed.
(read_char_minibuf_menu_prompt):
(read_key_sequence): Access buffer's downcase_table with XCHAR_TABLE.
(Fexecute_extended_command): Use Faref to access FUNCTION.
Use size_byte of BINDING.
(stuff_buffered_input): Use size_byte of STUFFSTRING.
(Fwrite_region): Use message_with_string.
(auto_save_error, Fdo_auto_save): Likewise.
(Ffile_name_directory): Maybe use make_unibyte_string.
(Ffile_name_nondirectory): Likewise.
(Fsubstitute_in_file_name): Convert substituted envvars to multibyte
if necessary. Otherwise use make_unibyte_string.
(Finsert_file_contents): Use make_unibyte_string.
(double_dollars): Use make_uninit_multibyte_string.
(Fstring): Use make_multibyte_string.
(Fcompose_string): Likewise.
(Ffind_charset_string): Handle bytes vs chars in string.
Special case for single-byte strings.
(Fchars_in_string): Function deleted.
(Fstring): Renamed from Fconcat_chars.
Handle bytes vs chars in string.
(syms_of_charset): Corresponding changes.
(oblookup): Take args SIZE and SIZE_BYTE. Callers changed.
(init_obarray, read1, make_symbol):
Pass new arg to make_pure_string.
(Fintern, oblookup, Fintern_soft, intern): Handle size_byte.
(dir_warning): Pass new arg to message_dolog.
(read1): PCH is now int *.
Declare ch as int.
(read0): Declare c as int.
(read_list): Declare ch as int.
(read0): Use Fmake_string not make_string.
(read1): When reading a string, maybe use make_unibyte_string.
(Fread_from_string): Convert string indices to/from bytes.
(insert_from_string_1, insert_from_buffer_1): Use it.
(copy_text): New function.
(insert_from_buffer_1): Call copy_text to convert between
single-byte and multibyte text.
(insert_from_string_1): Likewise.
(insert_1_both): New function.
(insert_from_string): New args POS_BYTE, LENGTH.
(insert_from_string_before_markers):
(insert_from_string_1): New arg POS_BYTE. Swap args NCHARS, NBYTES.
Don't fail to use POS_BYTE!
(insert_from_buffer_1): Get both inschars and insbytes from NEW.
(Fsubstring): Use make_multibyte_string.
(concat, Fsubstring, internal_equal, mapcar1):
Distinguish bytes and chars when indexing strings.
(Fstring_equal, Fstring_lessp): Likewise.
(substring_both): New function.
(string_make_multibyte, string_make_unibyte): New functions.
(string_char_to_byte, string_byte_to_char): New functions.
check them for multibyteness, don't check enable-multibyte-characters.
(Fcall_process): Use size_byte for the args.
(Fcall_process_region): Likewise for temp file.
(child_setup, getenv_internal, Fgetenv): Likewise.
(read_process_output): New var `multibyte'.
Set it according to which coding system was used.
(read_process_output): Handle bytes vs chars.
(send_process): Use size_byte of OBJECT.
(Fprocess_send_string): Pass size_byte to send_process.
(print): When multibyte is disabled,
print multibyte string chars using hex escapes.
(printchar): Pass new arg to message_dolog.
(strout): New arg MULTIBYTE. Callers changed.
(strout): Take args SIZE and SIZE_BYTE;
operate on both chars and bytes.
(print_string): Pass new arg to strout.
If not using strout, fetch a whole multibyte char at once.
(write_string): Pass new arg to strout.
(write_string_1): Likewise.
(print) <case Lisp_String>: Scan by chars and bytes.
(print) <case Lisp_Symbol>: Scan name by chars and bytes.
(PRINTPREPARE): Use make_multibyte_string.
Initialize print_buffer_pos_byte. Use insert_1_both.
(printchar): Update print_buffer_pos_byte and print_buffer_pos.
(print_buffer_pos_byte): New variable.
