Fix misuses of NULL when talking about the NUL character

* lisp/subr.el (inhibit-null-byte-detection): Make it an obsolete alias.

* src/coding.c (setup_coding_system): Use new name.
(detect_coding): Rename null_byte_found => nul_byte_found.
(detect_coding_system): Use new name.
Rename null_byte_found => nul_byte_found.
(Fdefine_coding_system_internal): Use new name.
(syms_of_coding): Rename inhibit-null-byte-detection to
inhibit-nul-byte-detection.
* src/w16select.c (get_clipboard_data): null_char => nul_char.
* src/json.c (check_string_without_embedded_nuls): Rename from
check_string_without_embedded_nulls.
(Fjson_parse_string): Adjust accordingly.
* src/coding.h (enum define_coding_undecided_arg_index)
(enum coding_attr_index): ...null_byte... => ...nul_byte....
* lisp/info.el (info-insert-file-contents, Info-insert-dir):
* lisp/international/mule.el (define-coding-system):
* lisp/vc/vc-git.el (vc-git--call):
* doc/lispref/nonascii.texi (Lisp and Coding Systems): Use the new name.

1 files changed, 3 insertions, 3 deletions

diff --git a/src/coding.h b/src/coding.h
index 58e12d6176a..e38c0ee3968 100644
--- a/src/coding.h
+++ b/src/coding.h
@@ -82,7 +82,7 @@ enum define_coding_ccl_arg_index
 
 enum define_coding_undecided_arg_index
   {
-    coding_arg_undecided_inhibit_null_byte_detection = coding_arg_max,
+    coding_arg_undecided_inhibit_nul_byte_detection = coding_arg_max,
     coding_arg_undecided_inhibit_iso_escape_detection,
     coding_arg_undecided_prefer_utf_8,
     coding_arg_undecided_max
@@ -137,7 +137,7 @@ enum coding_attr_index
 
     coding_attr_emacs_mule_full,
 
-    coding_attr_undecided_inhibit_null_byte_detection,
+    coding_attr_undecided_inhibit_nul_byte_detection,
     coding_attr_undecided_inhibit_iso_escape_detection,
     coding_attr_undecided_prefer_utf_8,
 
@@ -351,7 +351,7 @@ struct emacs_mule_spec
 
 struct undecided_spec
 {
-  /* Inhibit null byte detection.  1 means always inhibit,
+  /* Inhibit NUL byte detection.  1 means always inhibit,
      -1 means do not inhibit, 0 means rely on user variable.  */
   int inhibit_nbd;