$ perl -E 'open $fh, "<a.txt"; $fh->seek(0, 0);'
Can't locate object method "seek" via package "IO::Handle" at -e line 1.

##</code><code>##

$ perl -MFileHandle -E 'open $fh, "<a.txt"; $fh->seek(0, 0);'

##</code><code>##

seek $fh, 0, 0;