I'm not too sure what you want to do. But if you want all matches except the
first I would get all the matches and just get rid of the first one.
If you want to really match the word "STRUCT" then use something like this:

use strict;
use warnings;

my $dat="0011222STRUCTdata1...............02121STRUCTdata2..........02
+342STRUCTdata3";
my @m;

@m = $dat =~ /STRUCT/g;
shift (@m);
foreach (@m) {print "$_\n"};
[download]

If you want to match the data between the "STRUCT" then try one of these:
(excluding the data1 part. If you need it just delete one of the shift)

@m = $dat =~ /(.*?)(?:STRUCT|$)/g;
shift (@m);
shift (@m);
foreach (@m) {print "$_\n"};

@m = split(/STRUCT/, $dat);
shift(@m);
shift(@m);
foreach (@m) {print "$_\n"};
[download]

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