(Ffind_operation_coding_system): Docstring improved.

(syms_of_coding): Docstring of `file-coding-system-alist' improved.

src/ChangeLog

+2007-06-26  Kenichi Handa  <handa@m17n.org>
+
+	* coding.c (Ffind_operation_coding_system): Docstring improved.
+	(syms_of_coding): Docstring of `file-coding-system-alist' improved.
+
 2007-06-25  David Kastrup  <dak@gnu.org>
 	* keymap.c (Fcurrent_active_maps): Add `position' argument.

src/coding.c

@@ -7464,6 +7464,8 @@ They may specify a coding system, a cons of coding systems,
 or a function symbol to call.
 In the last case, we call the function with one argument,
 which is a list of all the arguments given to this function.
+If the function can't decide a coding system, it can return
+`undecided' so that the normal code-detection is performed.
 
 If OPERATION is `insert-file-contents', the argument corresponding to
 TARGET may be a cons (FILENAME . BUFFER).  In that case, FILENAME is a
@@ -7967,7 +7969,9 @@ and the cdr part is used for encoding.
 If VAL is a function symbol, the function must return a coding system
 or a cons of coding systems which are used as above.  The function is
 called with an argument that is a list of the arguments with which
-`find-operation-coding-system' was called.
+`find-operation-coding-system' was called.  If the function can't decide
+a coding system, it can return `undecided' so that the normal
+code-detection is performed.
 
 See also the function `find-operation-coding-system'
 and the variable `auto-coding-alist'.  */);