Integrate perlio:
Jarkko Hietaniemi [Sat, 20 Oct 2001 15:14:25 +0000 (15:14 +0000)]
[ 12532]
Extract doio.c's open(2) mode to string conversion as PerlIO_intmod2str()
Use for non-PERLIO fdupopen().

p4raw-link: @12532 on //depot/perlio: 06c7082d6226d352105bade1a7e185ff0a49e896

p4raw-id: //depot/perl@12534


Trivial merge