fr_mttl
{ DOALL(fr->fr_ttl = $2; fr->fr_mttl = 0xff;) }
YY_NUMBER { DOREM(fr->fr_ttl = $1; fr->fr_mttl = 0xff;) }
{ DOREM(fr->fr_ttl = $3; fr->fr_mttl = 0xff;) }