Function SocketSelect() Professional
Determines the status of one or more sockets and waits, if necessary.
SocketSelect( [<nReadFD>] , ; [<nWriteFD>] , ; [<nExceptFD>], ; [<aTimeOut>] , ; [@<nError>] ) --> nNumberOfSockets
The function returns the total number of sockets that are ready and contained in the descriptor sets, or zero if the time limit expired. When an error occurs, a value of SOCKET_ERROR is returned.
This function monitors activity on groups of sockets to see if any sockets are ready for reading or writing, or if exceptional messages are pending (out-of-band data). Sockets are grouped by descriptor sets whose handles must be provided as parameters.
The parameter <nReadFD> identifies those sockets of the descriptor set which are to be checked for readability. Readability is given under the following conditions:
The parameter <nWriteFD> identifies the sockets to be checked for writability.
The presence of out-of-band data or any exceptional error conditions is checked for the sockets identified by <nExceptFD>. This applies to:
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