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| <h4 class="subsection">16.9.4 Who is Connected to Me?</h4> |
| |
| <!-- sys/socket.h --> |
| <!-- BSD --> |
| <div class="defun"> |
| — Function: int <b>getpeername</b> (<var>int socket, struct sockaddr *addr, socklen_t *length-ptr</var>)<var><a name="index-getpeername-1803"></a></var><br> |
| <blockquote><p>The <code>getpeername</code> function returns the address of the socket that |
| <var>socket</var> is connected to; it stores the address in the memory space |
| specified by <var>addr</var> and <var>length-ptr</var>. It stores the length of |
| the address in <code>*</code><var>length-ptr</var>. |
| |
| <p>See <a href="Socket-Addresses.html#Socket-Addresses">Socket Addresses</a>, for information about the format of the |
| address. In some operating systems, <code>getpeername</code> works only for |
| sockets in the Internet domain. |
| |
| <p>The return value is <code>0</code> on success and <code>-1</code> on error. The |
| following <code>errno</code> error conditions are defined for this function: |
| |
| <dl> |
| <dt><code>EBADF</code><dd>The argument <var>socket</var> is not a valid file descriptor. |
| |
| <br><dt><code>ENOTSOCK</code><dd>The descriptor <var>socket</var> is not a socket. |
| |
| <br><dt><code>ENOTCONN</code><dd>The socket <var>socket</var> is not connected. |
| |
| <br><dt><code>ENOBUFS</code><dd>There are not enough internal buffers available. |
| </dl> |
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