Document once more the difference between :utf8

and :encoding(...).

p4raw-id: //depot/perl@16692

diff --git a/lib/open.pm b/lib/open.pm
index a5c337a..aab99fb 100644 (file)
--- a/lib/open.pm
+++ b/lib/open.pm
@@ -208,6 +208,13 @@ and these
     use open ':encoding(iso-8859-7)';
     use open IO => ':encoding(iso-8859-7)';
 
+The matching of encoding names is loose: case does not matter, and
+many encodings have several aliases.  See L<Encode::Supported> for
+details and the list of supported locales.
+
+Note that C<:utf8> discipline must always be specified exactly like
+that, it is not subject to the loose matching of encoding names.
+
 When open() is given an explicit list of layers they are appended to
 the list declared using this pragma.
 

diff --git a/pod/perluniintro.pod b/pod/perluniintro.pod
index 6e39125..68fb0fa 100644 (file)
--- a/pod/perluniintro.pod
+++ b/pod/perluniintro.pod
@@ -316,6 +316,11 @@ and on already open streams use C<binmode()>:
     binmode(STDOUT, ":encoding(UTF-8)");
     binmode(STDOUT, ":encoding(shift_jis)");
 
+The matching of encoding names is loose: case does not matter, and
+many encodings have several aliases.  Note that C<:utf8> discipline
+must always be specified exactly like that, it is not subject to the
+loose matching of encoding names.
+
 See L<PerlIO> for the C<:utf8> layer;
 L<PerlIO::encoding> and L<Encode::PerlIO> for the C<:encoding()> layer;
 L<Encode::Supported> for many encodings supported by the C<Encode> module.