in reply to Parse string and extract word after specific pattern

my $string = "stash_ST1.2.3.4_1.ROLLBACK.check.20170228-101051.435944.
+txt";
# find one or more not "." between pair of "."s following word ROLLBAC
+K
my ($word) = $string =~ m/ROLLBACK\.([^\.]+)\./; 
print "$word\n";  # prints "check"

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