Simple. What you want is: 
#!/usr/bin/perl

use open IN => ":utf8";

# Now all file handles opened for input (including ARGV)
# will use utf8 encoding unless told otherwise

while (<>) {
    do_whatever( $_ );
}

[download]
If you want specifically want binmode (not utf8) use ":raw" instead. The book suggests this may only be workable in newer versions of Perl. Works for me using v5.8.5

In reply to Re: Using binmode on ARGV filehandle? by ruzam
in thread Using binmode on ARGV filehandle? by graff

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