getsockopt or setsockopt (BPX1OPT, BPX4OPT) — Get or set options associated with a socket

Function

The getsockopt or setsockopt callable service gets or sets options that are associated with a socket.

Requirements

Operation	Environment
Authorization:	Supervisor state or problem state, any PSW key
Dispatchable unit mode:	Task or SRB
Cross memory mode:	PASN = HASN
AMODE (BPX1OPT):	31-bit task or SRB mode
AMODE (BPX4OPT):	64-bit task mode only
ASC mode:	Primary mode
Interrupt status:	Enabled for interrupts
Locks:	Unlocked
Control parameters:	All parameters must be addressable by the caller and in the primary address space.

Format

CALL BPX1OPT,(Socket_descriptor,
              Operation,
              Level,
              Option_name,
              Option_data_length,
              Option_data,
              Return_value,
              Return_code,
              Reason_code)

AMODE 64 callers use BPX4OPT with the same parameters.

Parameters

Socket_descriptor

Supplied parameter

Type:: Integer
Length:: Fullword

The name of a fullword that contains the socket file descriptor for which the service is to be performed.

Operation

Supplied parameter

Type:: Integer
Length:: Fullword

The name of a field that contains the operation option. The value of this field determines whether the service to be performed is getsockopt, setsockopt, or setibmsockopt. See BPXYSOCK — Map SOCKADDR structure and constants for valid Operation values.

Level

Supplied parameter

Type:: Integer
Length:: Fullword

The name of a field that contains the level for which the option is set or being set.

Option_name

Supplied parameter

Type:: Integer
Length:: Fullword

The name of a field in which the value of the option name is provided. See BPXYSOCK — Map SOCKADDR structure and constants for valid Option_name values.

Option_data_length

Supplied and returned parameter

Type:: Integer
Length:: Fullword

The name of a field that contains the length of Option_data. On return from getsockopt, this field contains the size of the data that was returned in Option_data. The size of this field should be less than 4096 bytes (4KB) in length. The size of the buffer specified should be the maximum length that the option_data could be on output.

Option_data

Supplied and returned parameter

Type:: Character
Length:: Length specified by Option_data_length.

The name of a field that contains the data that is associated with or is to be associated with the socket. On return from getsockopt, this field contains the data that is associated with the socket. For setsockopt, this field provides the data that is to be associated with the socket.

Return_value

Returned parameter

Type:: Integer
Length:: Fullword

The name of a fullword in which the getsockopt or setsockopt service returns one of the following:

0 if the request is successful.
-1 if the request is not successful.

Return_code

Returned parameter

Type:: Integer
Length:: Fullword

The name of a fullword in which the getsockopt or setsockopt service stores the return code. The getsockopt or setsockopt service returns Return_code. only if Return_value is -1. For a complete list of possible return code values, see z/OS UNIX System Services Messages and Codes. The getsockopt or setsockopt service can return one of the following values in the Return_code parameter:

Return_code	Explanation
EDOM	An argument that is too large was supplied on the call.
EINVAL	An incorrect argument was supplied on the call. Consult Reason_code to determine the exact reason the error occurred. The following reason code can accompany the return code: JRLevelNotSupp.
ENOBUFS	A buffer could not be obtained. Consult Reason_code to determine the exact reason the error occurred. The following reason code can accompany the return code: JROutofSocketCells.
ENOPROTOOPT	An option_name that was specified for getsockopt is not supported. An incorrect value was specified on the Level parameter. SOL_SOCKET must be specified. Consult Reason_code to determine the exact reason the error occurred. The following reason codes can accompany the return code: JRLevelNotSupp, JRInvalOpOpt, JROptNotSupp.
ENOSYS	For AF_UNIX, setsockopt was specified; it is not supported. Consult Reason_code to determine the exact reason the error occurred. The following reason code can accompany the return code: JRSetNotSupp.
ENOTSOCK	Socket_descriptor does not refer to a valid socket descriptor. Consult Reason_code to determine the exact reason the error occurred. The following reason code can accompany the return code: JRMustBeSocket.

Reason_code

Returned parameter

Type:: Integer
Length:: Fullword

The name of a fullword in which the getsockopt or setsockopt service stores the reason code. The getsockopt or setsockopt service returns Reason_code only if Return_value is -1. Reason_code further qualifies the Return_code value. For the reason codes, see z/OS UNIX System Services Messages and Codes.

Usage notes

The socket descriptor must refer to an open socket.
For AF_UNIX sockets, the getsockopt() service supports the following option_names only: so_acceptconn, so_type, and so_secinfo.
The level of support for this service depends on the particular socket stack you have installed. Some options might not be defined by the BPXYSOCK macro. Refer to the documentation for the product you are using to determine the socket options it supports. For example, see z/OS Communications Server: IP Sockets Application Programming Interface Guide and Reference for the z/OS® Communications Server socket stack, and z/OS Communications Server: IPv6 Network and Application Design Guide for information on IPv6 socket options.
See Callable services available to SRB mode routines for more information about programming considerations for SRB mode.

Characteristics and restrictions

There are no restrictions on the use of the getsockopt or setsockopt service.

Examples

For an example using this callable service, see BPX1OPT (getsockopt or setsockopt) example.