Change 13051 by jhi@alpha on 2001/11/16 15:26:41
Update perluniintro on the UTF-8 output matters
(that -w will warn unless the stream is explicitly UTF-8-ified).
Affected files ...
.... //depot/perl/pod/perluniintro.pod#2 edit
Differences ...
==== //depot/perl/pod/perluniintro.pod#2 (text) ====
Index: perl/pod/perluniintro.pod
--- perl/pod/perluniintro.pod.~1~ Fri Nov 16 08:30:05 2001
+++ perl/pod/perluniintro.pod Fri Nov 16 08:30:05 2001
@@ -236,11 +236,19 @@
Normally writing out Unicode data
- print chr(0x100), "\n";
+ print FH chr(0x100), "\n";
+
+will print out the raw UTF-8 bytes, but you will get a warning
+out of that if you use C<-w> or C<use warnings>. To avoid the
+warning open the stream explicitly in UTF-8:
+
+ open FH, ">:utf8", "file";
+
+and on already open streams use C<binmode()>:
-will print out the raw UTF-8 bytes.
+ binmode(STDOUT, ":utf8");
-But reading in correctly formed UTF-8 data will not magically turn
+Reading in correctly formed UTF-8 data will not magically turn
the data into Unicode in Perl's eyes.
You can use either the C<':utf8'> I/O discipline when opening files
@@ -251,11 +259,11 @@
The I/O disciplines can also be specified more flexibly with
the C<open> pragma; see L<open>:
- use open ':utf8'; # input and output will be UTF-8
- open X, ">utf8";
- print X chr(0x100), "\n"; # this would have been UTF-8 without the pragma
+ use open ':utf8'; # input and output default discipline will be UTF-8
+ open X, ">file";
+ print X chr(0x100), "\n";
close X;
- open Y, "<utf8";
+ open Y, "<file";
printf "%#x\n", ord(<Y>); # this should print 0x100
close Y;
@@ -329,7 +337,8 @@
close F;
If you run this code twice, the contents of the F<file> will be twice
-UTF-8 encoded. A C<use open ':utf8'> would have avoided the bug.
+UTF-8 encoded. A C<use open ':utf8'> would have avoided the bug, or
+explicitly opening also the F<file> for input as UTF-8.
=head2 Special Cases
End of Patch.
