$ 
$ # list the files in current directory
$ ls -1
compare_and_print.pl
comp_file
well_list
$ 
$ # show the contents of the "well_list" and "comp_file" files
$ cat well_list
TEST_WELL_01
TEST_WELL_02
TEST_WELL_11
TEST_WELL_22
GOV_WELL_1
GOV_WELL_201
PUB_WELL_57
PUB_WELL_82
$ 
$ cat comp_file
/drive/t/Asset/13_Wells/Test_Well_1/LAS_and_LIS/LL3.LIS
/drill/t/Cnt-143/Wells/Gov_Well_201/Drilling/Government_Well_Mnemonics.dlis
/drill/t/Cnt-143/Wells/Gov_Well_201/Drilling/LL3_0893780002.LIS
/drive/t/Asset/13_Wells/Test_Well_011/LAS_and_LIS/LL3_9367000.LIS
/drive/r/Asset/13_Wells/Test_Well_01/LAS_and_LIS/LL3_9367000.LIS
/drill/t/Cnt-143/Wells/Gov_Well_01/Drilling/Government_Well_Mnemonics.dlis
/drive/w/Asset/13_Wells/Public_Well_82/County_82/NEUT&DN.LIS
$ 
$ # show the Perl program to compare these files and append results
$ cat -n compare_and_print.pl
     1	#!/usr/bin/perl -w
     2	use strict;
     3	
     4	# A hash to store the file names read from "well_list"
     5	my %files;
     6	my $file1 = "well_list";
     7	my $file2 = "comp_file";
     8	
     9	# Read "well_list" and set up a hash key that can be compared easily with
    10	# "comp_file". For a line like "TEST_WELL_01", the hash key would be
    11	# "test_well_1" i.e. lower case for the text joined with the integer value of
    12	# the last number. The value of this key is the actual line itself, since we
    13	# need this to create the file of this name. Thus, after reading line
    14	# "TEST_WELL_01" the hash would look like this:
    15	#     $files{"test_well_1"} = "TEST_WELL_01"
    16	open(FH, "<", $file1) or die "Can't open $file1: $!";
    17	while (<FH>) {
    18	    chomp;
    19	    my $val = $_;
    20	    /^(.*)_(.*?)$/;
    21	    my $key = lc($1)."_".int($2);
    22	    $files{$key} = $val;
    23	}
    24	close(FH) or die "Can't open $file1: $!";
    25	
    26	# Now read "comp_file". Split each line on "/" character. Then transform the
    27	# 5th token, the well name, as per the transformation rule above. That is,
    28	# lower case the text part joined with the integer value of the last number.
    29	# If this key exists in the hash %files, then open the file name derived
    30	# from the hash value and append the line we just read into the file.
    31	open(FH, "<", $file2) or die "Can't open $file2: $!";
    32	while (<FH>) {
    33	    chomp;
    34	    my $line = $_;
    35	    my @tokens = split("\/");
    36	    my ($txt, $num) = $tokens[5] =~ /^(.*)_(.*?)$/;
    37	    my $cmp = lc($txt)."_".int($num);
    38	    if (defined $files{$cmp}) {
    39	        print "Well found, appending to file: ", $line, "\n";
    40	        open(FH1, ">>", $files{$cmp}) or die "Can't open $files{$cmp}: $!";
    41	        print FH1 $line."\n";
    42	        close(FH1) or die "Can't close $files{$cmp}: $!";
    43	    } else {
    44	        print "Well not found               : ", $line, "\n";
    45	    }
    46	}
    47	close(FH) or die "Can't close $file2: $!";
    48	
$ 
$ # Run the Perl program
$ perl compare_and_print.pl
Well found, appending to file: /drive/t/Asset/13_Wells/Test_Well_1/LAS_and_LIS/LL3.LIS
Well found, appending to file: /drill/t/Cnt-143/Wells/Gov_Well_201/Drilling/Government_Well_Mnemonics.dlis
Well found, appending to file: /drill/t/Cnt-143/Wells/Gov_Well_201/Drilling/LL3_0893780002.LIS
Well found, appending to file: /drive/t/Asset/13_Wells/Test_Well_011/LAS_and_LIS/LL3_9367000.LIS
Well found, appending to file: /drive/r/Asset/13_Wells/Test_Well_01/LAS_and_LIS/LL3_9367000.LIS
Well found, appending to file: /drill/t/Cnt-143/Wells/Gov_Well_01/Drilling/Government_Well_Mnemonics.dlis
Well not found               : /drive/w/Asset/13_Wells/Public_Well_82/County_82/NEUT&DN.LIS
$ 
$ 
$ # now check if new files were created by the Perl program
$ ls -1
compare_and_print.pl
comp_file
GOV_WELL_1
GOV_WELL_201
TEST_WELL_01
TEST_WELL_11
well_list
$ 
$ # check the contents of the new files
$ cat GOV_WELL_1
/drill/t/Cnt-143/Wells/Gov_Well_01/Drilling/Government_Well_Mnemonics.dlis
$ 
$ cat GOV_WELL_201
/drill/t/Cnt-143/Wells/Gov_Well_201/Drilling/Government_Well_Mnemonics.dlis
/drill/t/Cnt-143/Wells/Gov_Well_201/Drilling/LL3_0893780002.LIS
$ 
$ cat TEST_WELL_01
/drive/t/Asset/13_Wells/Test_Well_1/LAS_and_LIS/LL3.LIS
/drive/r/Asset/13_Wells/Test_Well_01/LAS_and_LIS/LL3_9367000.LIS
$ 
$ cat TEST_WELL_11
/drive/t/Asset/13_Wells/Test_Well_011/LAS_and_LIS/LL3_9367000.LIS
$ 
$