foreach my $line (@lines) {

    if ($line =~ m/\[foo\]/) {
        print $line; # I do not want this line
        # how do I print the next lines in @lines
        # until I reach [foo2]?

        # once I get to [foo2] I want to print out
        # everything there also
    }
}

##</code><code>##

;
; foo file
;
[foo]
a=1
b=2
c=3
[foo2]
d=4
e=5
f=6