Introduce the double-diamond operator <<>>

This operator works like <> or <ARGV>, as it reads the list of file
names to open from the command-line arguments. However, it disables
the magic-open feature (that forks to execute piped commands) :

    $ bleadperl -e 'while(<>){print}' 'echo foo |'
    foo
    $ bleadperl -e 'while(<<>>){print}' 'echo foo |'
    Can't open echo foo |: No such file or directory at -e line 1.

1 files changed, 1 insertions, 1 deletions

diff --git a/proto.h b/proto.h
index 4f36b276cd..bd6234ff21 100644
--- a/proto.h
+++ b/proto.h
@@ -3100,7 +3100,7 @@ PERL_CALLCONV STRLEN *	Perl_new_warnings_bitfield(pTHX_ STRLEN *buffer, const ch
 #define PERL_ARGS_ASSERT_NEW_WARNINGS_BITFIELD	\
 	assert(bits)
 
-PERL_CALLCONV PerlIO*	Perl_nextargv(pTHX_ GV* gv)
+PERL_CALLCONV PerlIO*	Perl_nextargv(pTHX_ GV* gv, bool nomagicopen)
 			__attribute__nonnull__(pTHX_1);
 #define PERL_ARGS_ASSERT_NEXTARGV	\
 	assert(gv)