If this is all you want to do with those files, you could just hand this off as a system command, like so: 
`more B.txt >> A.txt`

[download]
See perlop if you're not familiar with "backtick" notation.

In reply to Re: How to concatenate the contents of two files? by crashtest
in thread How to concatenate the contents of two files? by yankeeblue

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