Well, this answer is almost a whole year late, no doubt because everyone was confused by your question. I too am a bit confused, but that's never stopped me from sticking my foot in my mouth before, so here goes: 
use strict;
use warnings;
use File::Basename;
use Acme::Don::t;

my $in_path  = '/path/to/input/file';
my $out_path = '/path/to/output/file';
my $in_file  = 'foo.csv';
my $out_file = fileparse($in_file,'\..*') . '.txt';

open IN, "$in_path/$in_file" or die "can't read $in_file: $!";
don't {'do anything but loop'} while <IN>;

open OUT, ">$out_path/$out_file" or die "can't write $out_file: $!";
print OUT "filename: $in_file\nlines: $.\n";

[download]
Check out perlvar to learn what $. is.

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to (jeffa) Re: How can I open a file from a source and read filename & counts? by jeffa
in thread How can I open a file from a source and read filename & counts? by icezero

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