Integrate perlio:
Jarkko Hietaniemi [Mon, 31 Dec 2001 14:17:55 +0000 (14:17 +0000)]
[ 13975]
perlio.c cleanup - in particular avoid accidental PerlIO_flush(NULL)
if PerlIONext is NULL.

p4raw-link: @13975 on //depot/perlio: 04892f7878d91125ce226bdf0d4e698521c1dfc5

p4raw-id: //depot/perl@13978


Trivial merge