SysSockSelect (FUN)¶

FUNCTION SysSockSelect : RTS_IEC_RESULT

Check a number of sockets for activity.

InOut:

Scope	Name	Type	Comment
Return	`SysSockSelect`	`RTS_IEC_RESULT`	Runtime system error code (see CmpErrors.library): ERR_OK ERR_SOCK_TIMEDOUT, if timeout expired
Input	`diWidth`	`DINT`	Number of sockets in the \|SOCKET_FD_SET\| structure, so \|SOCKET_FD_SETSIZE\| must be used here.
	`pfdRead`	POINTER TO SOCKET_FD_SET	Optional pointer to the structure \|SOCKET_FD_SET\| defining the socket set to be checked for reading. It is also possible to set this parameter to 0.
	`pfdWrite`	POINTER TO SOCKET_FD_SET	Optional pointer to the structure \|SOCKET_FD_SET\| defining the socket set to be checked for writing. It is also possible to set this parameter to 0.
	`pfdExcept`	POINTER TO SOCKET_FD_SET	Optional pointer to structure \|SOCKET_FD_SET\| that defines the socket set the error state has to be checked. It is also possible to set this parameter to 0.
	`ptvTimeout`	POINTER TO SOCKET_TIMEVAL	Pointer to maximum timespan which the function SysSockSelect waits for a response: ptvTimeout=NULL: Infinite wait ptvTimeout->tv_sec=-1, ptvTimeout->tv_usec=-1: Infinite wait ptvTimeout->tv_sec=0, ptvTimeout->tv_usec=0: No wait
	`pdiReady`	POINTER TO DINT	Number of sockets that are ready for IO