socket_accept - accept a connection on a socket

int socket_accept( int s, string | function read_callback, string | function write_callback );

This efun is only available if PACKAGE_SOCKETS is compiled in.

The argument s is a socket that has been created with socket_create(), bound to an address with socket_bind(), and is listening for connections after a socket_listen(). socket_accept() extracts the first connection on the queue of pending connections, creates a new socket with the same properties of s and allocates a new file descriptor for the socket. If no pending connections are present on the queue, socket_accept() returns an error as described below. The accepted socket is used to read and write data to and from the socket which connected to this one; it is not used to accept more connections. The original socket s remains open for accepting further connections.

The argument read_callback is the function or name of a function for the driver to call when the new socket (not the accepting socket) receives data.

The write callback should follow this format:

void read_callback(int fd)

Where fd is the socket which is ready to accept data.

The argument write_callback is the name of a function for the driver to call when the new socket (not the accepting socket) is ready to be written to. The write callback should follow this format:

void write_callback(int fd)

Where fd is the socket which is ready to be written to.

Note: The close_callback of the accepting socket (not the new socket) is called if the new socket closes unexpectedly, i.e. not as the result of a socket_close() call. The close callback should follow this format:

void close_callback(int fd)

Where fd is the socket which has closed.

socket_accept() returns a non-negative descriptor for the accepted socket on success. On failure, it returns a negative value. socket_error() can be used on the return value to get a text description of the error.

ERRORS - these definitions are in socket_err.h

EEFDRANGE Descriptor out of range.

EEBADF Descriptor is invalid.

EESECURITY Security violation attempted.

EEMODENOTSUPP Socket mode not supported.

EENOTLISTN Socket not listening.

EEWOULDBLOCK Operation would block.

EEINTR Interrupted system call.

EEACCEPT Problem with accept.

EENOSOCKS No more available efun sockets.

See also: socket_bind , socket_connect , socket_create , socket_listen