[11:34 bsb]$ perl -wl -e 'open A, "date|"; print scalar <A>'
Tue Mar 25 11:34:27 EST 2003

[11:34 bsb]$ perl -wl -MFatal=open -e 'open A, "date|"; print scalar <A>'
Name "main::A" used only once: possible typo at -e line 1.
Tue Mar 25 11:34:36 EST 2003

[11:34 bsb]$ perl -wl -MFatal=open -e 'open A, "date|"; print readline A'
Tue Mar 25 11:34:45 EST 2003