The CONNECT call is issued by a client to establish a connection between a local socket and a remote socket.
For UDP sockets, a CONNECT call need not precede an I/O call, but if issued, it allows you to send messages without specifying the destination.
The call sequence issued by the client and server for stream sockets is:
The caller must test the completion of the connection setup by calling SELECT and testing for the ability to write to the socket.
Authorization: | Supervisor state or problem state, any PSW key. |
Dispatchable unit mode: | Task. |
Cross memory mode: | PASN = HASN. |
Amode: | 31-bit or 24-bit. Note: See "Addressability
mode (Amode) considerations" under CALL instruction API environmental restrictions and programming requirements.
|
ASC mode: | Primary address space control (ASC) mode. |
Interrupt status: | Enabled for interrupts. |
Locks: | Unlocked. |
Control parameters: | All parameters must be addressable by the caller and in the primary address space. |
Figure 1 shows an example of CONNECT call instructions.
WORKING-STORAGE SECTION.
01 SOC-FUNCTION PIC X(16) VALUE IS 'CONNECT'.
01 S PIC 9(4) BINARY.
* IPv4 socket address structure.
01 NAME.
03 FAMILY PIC 9(4) BINARY.
03 PORT PIC 9(4) BINARY.
03 IP-ADDRESS PIC 9(8) BINARY.
03 RESERVED PIC X(8).
* IPv6 socket address structure.
01 NAME.
03 FAMILY PIC 9(4) BINARY.
03 PORT PIC 9(4) BINARY.
03 IP-ADDRESS PIC 9(8) BINARY.
03 FLOWINFO PIC 9(8) BINARY.
03 IP-ADDRESS.
10 FILLER PIC 9(16) BINARY.
10 FILLER PIC 9(16) BINARY.
03 SCOPE-ID PIC 9(8) BINARY.
01 ERRNO PIC 9(8) BINARY.
01 RETCODE PIC S9(8) BINARY.
PROCEDURE DIVISION.
CALL 'EZASOKET' USING SOC-FUNCTION S NAME ERRNO RETCODE.
For equivalent PL/I and assembler language declarations, see Converting parameter descriptions.