Integrate perlio:
Jarkko Hietaniemi [Sat, 8 Dec 2001 15:16:14 +0000 (15:16 +0000)]
[ 13531]
Tweak multi-arg open error messages

[ 13530]
Allow multi-arg open() if opening layer declares this legal.

p4raw-link: @13531 on //depot/perlio: 3b8752bbc2322bc61780a9c481ee2e3d71ae93ea
p4raw-link: @13530 on //depot/perlio: 7cf31bebccd8b4045fd1d586b26bef41a901c2d0

p4raw-id: //depot/perl@13534


Trivial merge