Improve documentation of Hexl mode

* doc/emacs/misc.texi (Editing Binary Files): Explain that Hexl can
also be used for editing text, including non-ASCII text.

diff --git a/doc/emacs/misc.texi b/doc/emacs/misc.texi
index 68941727f4ab1a5800bf5a6dfe9fae82be342ecb..dcbfd75f923f1ccc0f057a6d666245539cf734ea 100644 (file)
--- a/doc/emacs/misc.texi
+++ b/doc/emacs/misc.texi
@@ -2566,6 +2566,17 @@ Other Hexl commands let you insert strings (sequences) of binary
 bytes, move by @code{short}s or @code{int}s, etc.; type @kbd{C-h a
 hexl-@key{RET}} for details.
 
+  Hexl mode can also be used for editing text files.  This could come
+in handy if the text file includes unusual characters or uses unusual
+encoding (@pxref{Coding Systems}).  For this purpose, Hexl commands
+that insert bytes can also insert @acronym{ASCII} and
+non-@acronym{ASCII} characters, including multibyte characters.  To
+edit a text file with Hexl, visit the file as usual, and then type
+@w{@kbd{M-x hexl-mode @key{RET}}} to switch to Hexl mode.  You can now
+insert text characters by typing them.  However, inserting multibyte
+characters requires special care, to avoid the danger of creating
+invalid multibyte sequences: you should start typing such characters
+when point is on the first byte of a multibyte sequence in the file.
 
 @node Saving Emacs Sessions
 @section Saving Emacs Sessions