Hello, I noticed that one of my Perl scripts was generating truncated error messages when running on Windows. After some investigations, I found the problem was related to the way the Socket::getaddrinfo function returns the error message (maybe the same thing happens with Socket::getnameinfo).

Here is a code snippet to illustrate the problem:

require Socket;

# socktype is set to -1 to make getaddrinfo return an error
my ($gaiErr)=Socket::getaddrinfo('perl.org',80,{socktype => -1});
my ($osErr,$extErr)=($!,$^E);

print "\$gaiErr=\"$gaiErr\" (".($gaiErr+0).")\n";
print "\$osErr=\"$osErr\" (".($osErr+0).")\n";
print "\$extErr=\"$extErr\" (".($extErr+0).")\n";
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Here is what it returns when I run it on a Windows 10 21H1 19043.1586 system (configured in French), with Strawberry Perl 5.32.1-64bit:

$gaiErr="La prise en charge du type de socket spécifié n" (10044)
$osErr="Illegal byte sequence" (42)
$extErr="La prise en charge du type de socket spécifié n’existe pas da
+ns cette famille d’adresses" (10044)
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The error message contained in $gaiErr is truncated. It looks like at some point the getaddrinfo function tried to parse/process the error message returned by the corresponding Win32 API call, but it stopped when it encountered the "typographic apostrophe" / "right single quotation mark" character. I guess it didn't use the correct encoding (afaik it should use the Windows ANSI code page of the system). Note that in this case the $^E variable contains the entire correct error message...

For reference, here is the result when I run the same code on a Linux system:

$gaiErr="ai_socktype non supporté" (-7)
$osErr="No such file or directory" (2)
$extErr="No such file or directory" (2)
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This is the result I expected on Windows: the $gaiErr variable contains the entire error message, no need to check $! or $^E (which contains unrelated information in this case).

Maybe it is possible to workaround the problem by adding a line like this one (just after the getaddrinfo call):

$gaiErr=$^E=$gaiErr if($gaiErr && $^O eq 'MSWin32');

But I'm not sure it would always work (it would require all getaddrinfo error code values to be "compatible" with $^E). And anyway it seems a bit ugly... Did I miss something here? Also, is there a way to force usage of unlocalized error messages on Windows from a Perl script?

Thanks !