open ( FH, "p.txt" );
my @output = <FH>;
close ( FH );

#find the line which has "myFiles" in it
my @line = grep ( /myFiles/ ), @output;

#hopefully I should only one line back
my $i = $line[0];


#will this work?
$i =~ s/.*(test.*\.txt).*/test29-01-05\.txt/