dtcb — Apollo

10.4;dtcb (dump TCP control blocks), revision 2.0, 91/10/14
dtcb (dump TCP control blocks) -dump contents of tcp control blocks
usage: /etc/dtcb [-f] [-m] [-p] [ -a | -d | -u [<ucb_addr> | -t [<tcb_addr>] ]



DESCRIPTION
     The command dtcb dumps the contents of the TCP control blocks associated
     with a particular TCP connection.  Two control blocks are dumped: the UCB
     (user control block), which contains the send and receive queues and
     user-related flags; and the TCB (TCP control block), which contains the
     connection sequence numbers, state, flags, and out-of-sequence queues.
     Obtain the address of the TCB to be dumped by using the tcpstat -A
     command.  The TCB is listed under the column headed with PCB.  Obtain the
     UCB for a socket by executing the dtcb command on the socket's TCB.

OPTIONS
     -f             Force output if tcpd not running.

     -m             Print both TCB and UCB for a single socket.

     -p             Print the PID, GID, and process name of the process that
                    created the socket.

     -a             Print both TCB and UCB for all sockets.

     -d             Print the UCB or TCB for all sockets that have SO_DEBUG
                    enabled -- for example, FTP data connections opened with
                    the ftp debug command or TELNET connections opened with
                    the telnet -d command.

     -u <ucb_addr>  Print the UCB specified by the hexadecimal address
                    <ucb_addr> or, if no address is specified, all UCBs.

     -t <tcb_addr>  Print the TCB specified by the hexadecimal address
                    <tcb_addr> or, if no address is specified, all TCBs.

EXAMPLES
     The dump of a TCP control block for a listening FTP connection might look
     like this:

     $ /etc/dtcb -m -t e9064d4
     ############################################
     ----------  TCB at e9064d4    UCB at e90786c:
     lport 0  fport 0
     t_state ESTAB
     irs     24A3A08B  rcv_urp 24A3A08B  rcv_urg 24A3A08C  rcv_nxt 24A3A0A6
        rcv_end 00000000
     iss     251A4222  seq_fin 251A4222  snd_end 251A42B8  snd_urp 00000000
        snd_lst 251A42B8
     snd_nxt 251A42B8  snd_una 251A42B8  snd_wl  24A3A0A6  snd_hi  251A42B8
     rex_val 251A42B8  rtl_val 251A42B8  xmt_val 251A429B
     tcb flags:
     SYN_ACKED SYN_RCVD
     snd_wnd 9116  maxseg 1420  xmtime 3  rxtct 0
     timers:
     INIT 0  REXMT 0  REXMTTL 0  PERSIST 0  FINACK 0
     t_rcv_next E9064D4  t_rcv_prev E9064D4

     ----------  UCB at e90786c  TCB at e9064d4:
     local 192.9.99.4.21   host  192.9.99.3.1026
     uc_snd 9116  uc_ssize 0  uc_rcv 9116  uc_rsize 0
     uc_shead 0  uc_stail 0  uc_rhead 0  uc_rtail 0
     uc_srcif itr0  uc_refcnt 0
     uc_qhead 0  uc_gway 0
     uc_q0 0
     uc_q 0
     uc_xflag   (0001):  ULINKED
     uc_iostate (2000):  IS_CONNECTED
     uc_status  (0000):
     uc_flags   (0002):  UTCP
     uc_options (0104):  SO_REUSEADDR SO_OOBINLINE
     uc_error 0  uc_xstat 0  uc_backlog 0
     oobmark 0  oobcnt 0


SEE ALSO
     Configuring and Managing TCP/IP.
Museum
