AIF Enhancement to AIFPROCGET Details

by John Berry
Commercial Systems Division

Overview

This article provides more detailed information on the AIFPROCGET enhancement, introduced in the article, "AIF Enhancement to AIFPROCGET Overview," in Chapter 3, "System Management."

AIFPROCGET, item 2149, was enhanced to retrieve information on sockets owned by a given process (pin or pid). This item can be used to request information on all or just incoming socket connections belonging to a process. The maximum number of sockets that can be opened per process is currently 1,024.

connection_type Record Type

A pointer to the record type, connection_type, must be passed into the AIFPROCGET parameter list. The caller is responsible for initializing the connection_type. Each entry has the following type definitions: 


connection_type = 


   packed record
     cnt    : integer;
     mode   : integer;
     entry  : array[1..n] of conn_element_type;
   end;


Record size:  4 + 4 + 20n bytes
Alignment  :  4 bytes


n represents a user-defined size.

Field descriptions for the connection_type record structure are as follows:

cnt
Maximum number of socket connections to return. On input, the cnt field represents the number of allowable elements in the entry array. On return, the cnt field will contain the actual number of socket connections.

mode
Determines which type of socket connections to return. Currently, it returns all or just incoming connections.

The mode field can be initialized with one of two constants: 

0   When 0 is passed, all connections are returned.  


1   When 1 is passed, incoming connections are returned.

conn_element_type
Connection information record. See the next section, "conn_element_type Field," for more details.

Once AIFPROCGET returns, an array of connection entries are available in the connection_type record structure. Each entry has the following type definition: 


conn_element_type =


                    packed record
                      local_ip_addr   : bit32;
                      remote_ip_addr  : bit32;
                      local_sap       : bit16;
                      remote_sap      : bit16;
                      socket_state    : shortint;
                      flags           : flag_type;    
                      protocol        : bit8;
                      socket_type     : bit8;
                      filler          : bit16;
                    end;

conn_element_type Field

Field descriptions for the conn_element_type record structure are as follows:

local_ip_addr
IP address of the local HP 3000.
remote_ip_addr
IP address of the remote machine.
local_sap
local TCP port number in use.
remote_sap
TCP port number allocated on remote machine.
socket_state
Socket state.
flags
flag_type record.
protocol
Protocol being used.
socket_type
Type of socket being used.

The flags field in conn_element_type has the following record definition: 


flag_type = 


            packed record
              case integer of 
                1: (all                  : bit16);
                2: (select_supported     : boolean;
                    bsd_sk               : boolean;
                    catch_all_flag       : boolean;     
                    tcp_msg_mode         : boolean;
                    connection_initiator : boolean
                    filler               : bit11);
            end;

flags Field

Field descriptions for the flag_type record structure are as follows:

select_supported
True, if the select() function is supported on this socket.

bsd_sk
True, if the connection is through a BSD Socket. False, if the connection is through a NetIPC Socket.

catch_all_flag
True, if this is a NetIPC Socket using X.25 level 3 direct access and the socket was created with the catch_all_flag set.

tcp_msg_mode
True, if the connection is using TCP in message mode.

connection_initiator
True, if the local process initiated the connection.

The protocol, socket_type and socket_state fields in conn_element_type will return one of the following values: 


PROTOCOLS


  TRANSMISSION CONTROL PROTOCOL = 4
  USER DATAGRAM PROTOCOL        = 5
  PACKET EXCHANGE PROTOCOL      = 6


TYPES OF SOCKETS


  CONNECTION SOCKET = 0
  DATAGRAM SOCKET   = 1
  CALL SOCKET       = 3


SOCKET STATES


  INITIALIZED  = -1 
  CONNECTING   =  1
  WAIT_CONFIRM =  2  
  DUPLEX_OPEN  =  3  
  SIMPLEX_IN   =  4 
  SIMPLEX_OUT  =  5     
  CLOSED       =  6  
  CONN_ABORTED =  7 
  BOUND        =  8 
  LISTENING    =  9  
  SHUT         = 10
  LINGERING    = 11

socket_state Field

Descriptions for the values of the socket_state field are as follows:

INITIALIZED
Connection doesn't exist.
CONNECTING
IPCCONNECT called, waiting for IPCRECV.
WAIT_CONFIRM
IPCRECVCN done, user must accept/reject.
DUPLEX_OPEN
Connected, can send and receive data.
SIMPLEX_IN
Graceful close, can only receive.
SIMPLEX_OUT
Received graceful close, send only.
CLOSED
Both parties closed, user must shut down.
CONN_ABORTED
Connection aborted, user must shut down.
BOUND
Socket is bound to an address.
LISTENING
sk_listen has been called.
SHUT
Socket shutdown or encountered error.
LINGERING
Socket shutdown lingering pending.