socket_select/6¶

socket_select(+ SOCKETS, - NEWSTREAMS, + TIMEOUT, + STREAMS, - READSTREAMS)* [unsupported in YAP-6.3]

Interface to system call select, used for servers to wait for connection requests or for data at sockets. The variable SOCKETS is a list of form KEY-SOCKET, where KEY is an user-defined identifier and SOCKET is a socket descriptor. The variable TIMEOUT is either off, indicating execution will wait until something is available, or of the form SEC-USEC, where SEC and USEC give the seconds and microseconds before socket_select//55 returns. The variable SOCKETS is a list of form KEY-STREAM, where KEY is an user-defined identifier and STREAM is a stream descriptor

Execution of socket_select//55 unifies READSTREAMS from STREAMS with readable data, and NEWSTREAMS with a list of the form KEY-STREAM, where KEY was the key for a socket with pending data, and STREAM the stream descriptor resulting from accepting the connection.