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##

# listen Function

## C

    int listen(
        SOCKET s,
        int backlog
    );

## Description

This function sets the specified socket in a listen mode. Calling the listen function indicates that the application is ready to accept connection requests arriving at a socket of type SOCK_STREAM. The connection request is queued (if possible) until accepted with an accept function. The backlog parameter defines the maximum number of pending connections that may be queued.

## Preconditions

bind() must have been called on the s socket first.

## Parameters

Parameters | Description
--- | ---
s | Socket identifier returned from a prior socket() call.
backlog | Maximum number of connection requests that can be queued. Note that each backlog requires a TCP socket to be allocated.

## Returns

- 0 - The function was successful.
- SOCKET_ERROR (-1) - Function failed. errno is set accordingly.

## Remarks

None.