NAME | SYNOPSIS | FEATURES | DESCRIPTION | RETURN VALUE | ATTRIBUTES | SEE ALSO | RESTRICTIONS
#include <sys/types.h> #include <sys/socket.h>int listen(int s, int backlog);
POSIX_SOCKETS
To accept connections, a socket is first created using socket(2POSIX). The ability to accept incoming connections and a queue limit for incoming connections are specified using listen. The connections are accepted using accept(2POSIX). The listen call applies only to sockets of type SOCK_STREAM.
The backlog parameter defines the maximum length of the queue of pending connections. If a connection request arrives when the queue is full, the client may receive an error message (ECONNREFUSED), or, if the underlying protocol supports retransmission, the request may be ignored to enable retries.
Upon successful completion, listen returns 0; otherwise it returns -1 and sets errno to indicate one of the following error conditions:
The s argument is not a valid descriptor.
The s argument is not a socket.
The socket is not of a type that supports the listen operation.
See attributes(5) for descriptions of the following attributes:
ATTRIBUTE TYPE | ATTRIBUTE VALUE |
---|---|
Interface Stability | Evolving |
The backlog is currently limited (silently) to 5.
NAME | SYNOPSIS | FEATURES | DESCRIPTION | RETURN VALUE | ATTRIBUTES | SEE ALSO | RESTRICTIONS