use strict;
use warnings;

my $file1Str = <<FILEDATA;
Alex 3 44
Barry 2 44
James 6 45
Drew 9 43
Alex 124 175
FILEDATA

my $file2Str = <<FILEDATA;
James 1 22
Alex 89 120
Alex 134 155
Barry 12 24
FILEDATA

my $file3Str = <<FILEDATA;
Alex 154 174
James 29 45
Drew 19 54
Drew 139 154
FILEDATA

open my $fileIn, '<', \$file1Str;
print "Prim: $_" for <$fileIn>;
close $fileIn;

for my $secFile ($file2Str, $file3Str) {
    open my $secIn, '<', \$secFile;
    print "Sec: $_" for <$secIn>;
}