I think OP's problems were sufficiently pointed out. I was wondering if lexical file handles (open my $fh vs. open FILE) might be useful. What I found was that I successfully separated the input filehandle pointer from the output filehandle pointer, but the input filehandle stopped at the original eof instead of moving on through the new file contents. Could some wiser monks explain that to me? 

C:\chas_sandbox>for %f in (a b c d) Do echo %f>>alpha.txt

C:\chas_sandbox>echo a 1>>alpha.txt

C:\chas_sandbox>echo b 1>>alpha.txt

C:\chas_sandbox>echo c 1>>alpha.txt

C:\chas_sandbox>echo d 1>>alpha.txt

C:\chas_sandbox>perl -le "open my $fh_in, '<', 'alpha.txt'; open my $f
+h_out, '>>
', 'alpha.txt';while (<$fh_in>) {chomp;print $fh_out chr(ord($_)+4); l
+ast if $_
eq 'v'}"

C:\chas_sandbox>type alpha.txt
a
b
c
d
e
f
g
h

[download]

#my sig used to say 'I humbly seek wisdom. '. Now it says:
use strict;
use warnings;
I humbly seek wisdom.

In reply to Re: read from a file and write into the same file by goibhniu
in thread read from a file and write into the same file by Anonymous Monk

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