He's using <> so the original text file is implicitly opened if given on the cmd line. I guess you already knew, but you may have just overlooked it.

To be sure, just take his code and modify it like thus: 

#!/usr/bin/perl -l

my @file = <>;
print 0+@file;

[download]

Indeed

$ ./bar.pl data.txt 
46
$ wc data.txt 
 46  36 346 data.txt

[download]

In reply to Re^2: extracting data and saving into seperate files by blazar
in thread extracting data and saving into seperate files by Angharad

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