Consider the following script, the source of which is encoded in UTF-8:
use utf8;
use open qw/:utf8 :std/;
my $str = "Käse\n";
print STDOUT $str;
print STDERR $str;
warn $str;
die $str;
On a UTF-8 terminal, this prints Käse three times. So far, so good. Now remove
the open pragma and execute the script using the -C switch, which is documented
as follows in perlrun as seen at http://perldoc.perl.org/perlrun.html:
----8<----
-C [number/list]
The -C flag controls some of the Perl Unicode features.
As of 5.8.1, the -C can be followed either by a number or a list of option
letters. The letters, their numeric values, and effects are as follows; listing
the letters is equal to summing the numbers.
• I 1 STDIN is assumed to be in UTF-8
• O 2 STDOUT will be in UTF-8
• E 4 STDERR will be in UTF-8
• S 7 I + O + E
----8<----
So -C7 or -CS should switch all channels to UTF-8. And they do, but only for
print, not for warn and die, which seem to remain unaffected by -C. I've seen
this behaviour for perl 5.8.9 and 5.10.1 for Darwin (Mac), as well as 5.8.7 and
5.8.9 for Linux.
Don't know if this is a bug or a feature in Perl, or if the Perldoc for the -C
switch should be updated to reflect the actual behaviour, which seems to be:
• E 4 STDERR will be in UTF-8, but
`die` and `warn` remain unaffected
--
Michael.Ludwig (#) XING.com
