From your description, I am not 100% sure about how your input data is structured, I assume all variables can appear in any one of the three key columns. A working solution would be as follows: (Sorry if it looks strange, I don't know how your data looks and have used your column widths of 25 and 15. I have just printed out the matches, of course you can e.g. save them in a hash or call a function immediately on them, depending on what you want to do with the data.) 
use strict;
use warnings;
#define a regexp matching the interesting variable names
my $interesting_vars = 
  qr(a111111111111111111111111|c222222222222222222222222);
#sample input rows
my @rows = ('a111111111111111111111111              1b8888888888888888
+888888888            15x222222222222222222222222              2', 
            'd999999999999999999999999              4b3333333333333333
+333333333            15c222222222222222222222222            123');

for (@rows) {
  #split by variable value pairs  
  for (/.{40}/g) {
    #split variable and value
    /(.{25})(.{15})/;
    #since I am doing an additional match, I have to
    #save my submatches
    my $var = $1;
    my $val = $2;
    print "'$var' = '$val'\n" 
      if $var =~ $interesting_vars;   
  }
}

[download]
Output: 
'a111111111111111111111111' = '              1'
'c222222222222222222222222' = '            123'

[download]

In reply to Re: Extracting specific data from fixed-width columns by jds17
in thread Extracting specific data from fixed-width columns by lunabelle22a

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