If each file really is "straight text, no carriage returns, no spaces, etc. " then all you have to do is the following from the command line: 
perl -pi -e '$_=">$ARGV\n$_\n"' *.txt

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This makes the assumption that all ".txt" files in your directory fit your criteria. "$ARGV" represents the current file being used if you are using the "<>" operator. When you use -p, perl assumes that there is a 
while(<>){}

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loop around your code and then prints $_ at the end of each iteration through the loop. The -i causes perl to be in "In-place edit" mode, which will cause each "print" statement without a filehandle to print to whatever file $ARGV currently is. CHANGE: As jmanning2k pointed out, I forgot to put ">" in front of the file name

In reply to Re: very basic, just beginning by fletcher_the_dog
in thread very basic, just beginning by MiamiGenome

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