if ((my $pid = fork) == 0) {
 $< = getpwnam "dbuser" || die "getpwnam: $!";
 $( = getgrnam "dbuser" || die "getgrnam: $!";
 exec "/bin/bash", "-i" or die "exec: $!";
} elsif ($pid > 0) {
 waitpid $pid, 0;
} else {
 die "fork: $!";
}