Pipes sends the data to the program's standard input, so you need: 
#!/usr/bin/perl
while (<STDIN>) {
   chomp;
   print "$_ and two\n";
}

[download]

But it's better to use the following since <> is more flexible. It reads from STDIN unless file names are specified on the command line (in which case it reads the named files instead). 

#!/usr/bin/perl
while (<>) {
   chomp;
   print "$_ and two\n";
}

[download]

In reply to Re: How do I use the output of one perls script as the input of another on the commandline? like a pipeline by ikegami
in thread How do I use the output of one perls script as the input of another on the commandline? like a pipeline by Gretter

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