fstat

USER     CMD          PID   FD MOUNT        INUM MODE       R/W    SZ|DV
_dhcp    dhcrelay   17341 text /usr       104215 -r-xr-xr-x   r    25432
_dhcp    dhcrelay   17341   wd /var        15362 drwxr-xr-x   r      512
_dhcp    dhcrelay   17341 root /var        15362 drwxr-xr-x   r      512
_dhcp    dhcrelay   17341   tr /home       26105 -rw-------  rw    11357
_dhcp    dhcrelay   17341    0 /            8761 crw-rw-rw-  rw     null
_dhcp    dhcrelay   17341    1 /            8761 crw-rw-rw-  rw     null
_dhcp    dhcrelay   17341    2 /            8761 crw-rw-rw-  rw     null
_dhcp    dhcrelay   17341    3 /            8100 crw-------  rw     bpf0
_dhcp    dhcrelay   17341    4* internet dgram udp 10.12.1.253:67 <-> 10.7.1.212:67

ktrace

17341          EMUL  "native"
 17341 dhcrelay RET   poll 1
 17341 dhcrelay CALL  gettimeofday(0x7f7ffffd9a90,0)
 17341 dhcrelay STRU  struct timeval { 1441267051<"Sep  3 10:57:31 2015">.163182 }
 17341 dhcrelay RET   gettimeofday 0
 17341 dhcrelay CALL  read(3,0x45594d20000,0x8000)
 17341 dhcrelay GIO   fd 3 read 364 bytes
 17341 dhcrelay RET   read 364/0x16c
 17341 dhcrelay CALL  sendto(4,0x7f7ffffd89e0,0x12c,0,0,0)
 17341 dhcrelay RET   sendto -1 errno 51 Network is unreachable
 17341 dhcrelay CALL  poll(0x456538e1c80,2,INFTIM)
 17341 dhcrelay RET   poll 1
 17341 dhcrelay CALL  gettimeofday(0x7f7ffffd9a90,0)
 17341 dhcrelay STRU  struct timeval { 1441267172<"Sep  3 10:59:32 2015">.497817 }
 17341 dhcrelay RET   gettimeofday 0
 17341 dhcrelay CALL  read(3,0x45594d20000,0x8000)
 17341 dhcrelay GIO   fd 3 read 364 bytes
 17341 dhcrelay RET   read 364/0x16c
 17341 dhcrelay CALL  sendto(4,0x7f7ffffd89e0,0x12c,0,0,0)
 17341 dhcrelay RET   sendto -1 errno 51 Network is unreachable
 17341 dhcrelay CALL  poll(0x456538e1c80,2,INFTIM)

ps

USER       PID %CPU %MEM   VSZ   RSS TT  STAT  STARTED       TIME COMMAND
_dhcp    17341  0.0  0.1   560   884 ??  Ss    23Aug15    0:00.17 /usr/sbin/dhcrelay -i vlan12 10.7.1.212