Unknown discipline ':utf8' w/ maint perl w/o perlio

Message-ID: <3F62301B.3080604@stason.org>

s/discipline/IO layer/, instead of "unknown" say "unavailable",
and have the fuller explanation in perldiag.

p4raw-id: //depot/perl@21203

1 files changed, 1 insertions, 1 deletions

diff --git a/doio.c b/doio.c
index da9cd80c39..353e2a9182 100644
--- a/doio.c
+++ b/doio.c
@@ -1165,7 +1165,7 @@ fail_discipline:
 		if (!end)
 		    end = s+len;
 #ifndef PERLIO_LAYERS
-		Perl_croak(aTHX_ "Unknown discipline '%.*s'", end-s, s);
+		Perl_croak(aTHX_ "IO layers (like '%.*s') unavailable", end-s, s);
 #else
 		s = end;
 #endif