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<a name="connectWithTimeout"></a>
<p align=right>
<a href="rtnIndex.htm"><i>OS Libraries :  Routines</i></a></p>

</blockquote><h1>connectWithTimeout(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong>connectWithTimeout(&nbsp;)</strong> - attempt socket connection within a specified duration</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>STATUS connectWithTimeout
    (
    int               sock,    /* socket descriptor */
    struct sockaddr * adrs,    /* addr of the socket to connect */
    int               adrsLen, /* length of the socket, in bytes */
    struct timeval *  timeVal  /* time-out value */
    )
</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
Use this routine as an alternative to <b><a href="./sockLib.html#connect">connect</a>(&nbsp;)</b> when your application
requires a shorter time out on a connection attempt.  By design, a TCP
connection attempt times out after 75 seconds if unsuccessful.  Thus, a 
blocking TCP socket <b><a href="./sockLib.html#connect">connect</a>(&nbsp;)</b> call might not return for 75 seconds.  A 
<b><a href="./sockLib.html#connectWithTimeout">connectWithTimeout</a>(&nbsp;)</b> call lets you reduce this time out by scheduling an 
abort of the connection attempt if it is not successful before <i>timeVal</i>.
However, <b><a href="./sockLib.html#connectWithTimeout">connectWithTimeout</a>(&nbsp;)</b> does not actually change the TCP timeout
value.  Thus, you cannot use <b><a href="./sockLib.html#connectWithTimeout">connectWithTimeout</a>(&nbsp;)</b> to lengthen the
connection time out beyond the TCP default.
<p>
In all respects other than the time out value, a <b><a href="./sockLib.html#connectWithTimeout">connectWithTimeout</a>(&nbsp;)</b> call 
behaves exactly like <b><a href="./sockLib.html#connect">connect</a>(&nbsp;)</b>. Thus, if no application is listening for 
connections at the other end, <b><a href="./sockLib.html#connectWithTimeout">connectWithTimeout</a>(&nbsp;)</b> returns immediately just 
like <b><a href="./sockLib.html#connect">connect</a>(&nbsp;)</b>.  If you specify a NULL pointer for <i>timeVal</i>, 
<b><a href="./sockLib.html#connectWithTimeout">connectWithTimeout</a>(&nbsp;)</b> behaves exactly like a <b><a href="./sockLib.html#connect">connect</a>(&nbsp;)</b> call.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
OK, or ERROR if a new connection is not established before timeout.
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./sockLib.html#top">sockLib</a></b>, <b><a href="./sockLib.html#connect">connect</a>(&nbsp;)</b>

<hr>
<a name="sendto"></a>
<p align=right>
<a href="rtnIndex.htm"><i>OS Libraries :  Routines</i></a></p>

</blockquote><h1>sendto(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong>sendto(&nbsp;)</strong> - send a message to a socket</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>int sendto
    (
    int               s,      /* socket to send data to */
    caddr_t           buf,    /* pointer to data buffer */
    int               bufLen, /* length of buffer */
    int               flags,  /* flags to underlying protocols */
    struct sockaddr * to,     /* recipient's address */
    int               tolen   /* length of <i>to</i> sockaddr */
    )
</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine sends a message to the datagram socket named by <i>to</i>.  The
socket <i>s</i> is received by the receiver as the sending socket.
<p>
The maximum length of <i>buf</i> is subject to the limits on UDP buffer
size. See the discussion of <b>SO_SNDBUF</b> in the <b><a href="./sockLib.html#setsockopt">setsockopt</a>(&nbsp;)</b> manual
entry.
<p>
You can OR the following values into the <i>flags</i> parameter with this
operation:
<p>
<dl>
<dt>
<b>MSG_OOB</b> (0x1)
<dd>
Out-of-band data.
<p>
<dt>
<b>MSG_DONTROUTE</b> (0x4)
<dd>
Send without using routing tables.
</dl>

<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
The number of bytes sent, or ERROR if the call fails.
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./sockLib.html#top">sockLib</a></b>, <b><a href="./sockLib.html#setsockopt">setsockopt</a>(&nbsp;)</b>

<hr>
<a name="send"></a>
<p align=right>
<a href="rtnIndex.htm"><i>OS Libraries :  Routines</i></a></p>

</blockquote><h1>send(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong>send(&nbsp;)</strong> - send data to a socket</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>int send
    (
    int          s,           /* socket to send to */
    const char * buf,         /* pointer to buffer to transmit */
    int          bufLen,      /* length of buffer */
    int          flags        /* flags to underlying protocols */
    )
</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine transmits data to a previously established connection-based
(stream) socket.
<p>
The maximum length of <i>buf</i> is subject to the limits
on TCP buffer size; see the discussion of <b>SO_SNDBUF</b> in the
<b><a href="./sockLib.html#setsockopt">setsockopt</a>(&nbsp;)</b> manual entry.
<p>
You may OR the following values into the <i>flags</i> parameter with this
operation:
<p>
<dl>
<dt>
<b>MSG_OOB</b> (0x1)
<dd>
Out-of-band data.
<p>
<dt>
<b>MSG_DONTROUTE</b> (0x4)
<dd>
Send without using routing tables.
</dl>

<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
The number of bytes sent, or ERROR if the call fails.
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./sockLib.html#top">sockLib</a></b>, <b><a href="./sockLib.html#setsockopt">setsockopt</a>(&nbsp;)</b>, <b><a href="./sockLib.html#sendmsg">sendmsg</a>(&nbsp;)</b>

<hr>
<a name="sendmsg"></a>
<p align=right>
<a href="rtnIndex.htm"><i>OS Libraries :  Routines</i></a></p>

</blockquote><h1>sendmsg(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong>sendmsg(&nbsp;)</strong> - send a message to a socket</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>int sendmsg
    (
    int             sd,       /* socket to send to */
    struct msghdr * mp,       /* scatter-gather message header */
    int             flags     /* flags to underlying protocols */
    )
</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine sends a message to a datagram socket.  It may be used in
place of <b><a href="./sockLib.html#sendto">sendto</a>(&nbsp;)</b> to decrease the overhead of reconstructing the
message-header structure (<b>msghdr</b>) for each message.
<p>
For BSD 4.4 sockets a copy of the <i>mp</i>->msg_iov array will be made.  This
requires a cluster from the network stack system pool of size 
<i>mp</i>->msg_iovlen * sizeof (struct iovec) or 8 bytes.
<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
The number of bytes sent, or ERROR if the call fails.
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./sockLib.html#top">sockLib</a></b>, <b><a href="./sockLib.html#sendto">sendto</a>(&nbsp;)</b>

<hr>
<a name="recvfrom"></a>
<p align=right>
<a href="rtnIndex.htm"><i>OS Libraries :  Routines</i></a></p>

</blockquote><h1>recvfrom(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong>recvfrom(&nbsp;)</strong> - receive a message from a socket</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>int recvfrom
    (
    int               s,       /* socket to receive from */
    char *            buf,     /* pointer to data buffer */
    int               bufLen,  /* length of buffer */
    int               flags,   /* flags to underlying protocols */
    struct sockaddr * from,    /* where to copy sender's addr */
    int *             pFromLen /* value/result length of <i>from</i> */
    )
</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine receives a message from a datagram socket regardless of
whether it is connected.  If <i>from</i> is non-zero, the address of the
sender's socket is copied to it.  The value-result parameter <i>pFromLen</i>
should be initialized to the size of the <i>from</i> buffer.  On return,
<i>pFromLen</i> contains the actual size of the address stored in <i>from</i>.
<p>
The maximum length of <i>buf</i> is subject to the limits on UDP buffer
size; see the discussion of <b>SO_RCVBUF</b> in the <b><a href="./sockLib.html#setsockopt">setsockopt</a>(&nbsp;)</b> manual
entry.
<p>
You may OR the following values into the <i>flags</i> parameter with this
operation:
<p>
<dl>
<dt>
<b>MSG_OOB</b> (0x1)
<dd>
Out-of-band data.
<p>
<dt>
<b>MSG_PEEK</b> (0x2)
<dd>
Return data without removing it from socket.
</dl>

<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
The number of number of bytes received, or ERROR if the call fails.
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./sockLib.html#top">sockLib</a></b>, <b><a href="./sockLib.html#setsockopt">setsockopt</a>(&nbsp;)</b>

<hr>
<a name="recv"></a>
<p align=right>
<a href="rtnIndex.htm"><i>OS Libraries :  Routines</i></a></p>

</blockquote><h1>recv(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong>recv(&nbsp;)</strong> - receive data from a socket</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>int recv
    (
    int    s,                 /* socket to receive data from */
    char * buf,               /* buffer to write data to */
    int    bufLen,            /* length of buffer */
    int    flags              /* flags to underlying protocols */
    )
</pre>

</blockquote><h4>DESCRIPTION</h4><blockquote><p>
This routine receives data from a connection-based (stream) socket.
<p>
The maximum length of <i>buf</i> is subject to the limits on TCP buffer
size; see the discussion of <b>SO_RCVBUF</b> in the <b><a href="./sockLib.html#setsockopt">setsockopt</a>(&nbsp;)</b> manual
entry.
<p>
You may OR the following values into the <i>flags</i> parameter with this
operation:
<p>
<dl>
<dt>
<b>MSG_OOB</b> (0x1)
<dd>
Out-of-band data.
<p>
<dt>
<b>MSG_PEEK</b> (0x2)
<dd>
Return data without removing it from socket.
</dl>

<p>
</blockquote><h4>RETURNS</h4><blockquote><p>
The number of bytes received, or ERROR if the call fails.
<p>
</blockquote><h4>SEE ALSO</h4><blockquote><p>
<b><a href="./sockLib.html#top">sockLib</a></b>, <b><a href="./sockLib.html#setsockopt">setsockopt</a>(&nbsp;)</b>

<hr>
<a name="recvmsg"></a>
<p align=right>
<a href="rtnIndex.htm"><i>OS Libraries :  Routines</i></a></p>

</blockquote><h1>recvmsg(&nbsp;)</h1> <blockquote></a></blockquote><h4>NAME</h4><blockquote>  
<p><strong>recvmsg(&nbsp;)</strong> - receive a message from a socket</p>

</blockquote><h4>SYNOPSIS</h4><blockquote><p>
<pre>int recvmsg
    (
    int             sd,       /* socket to receive from */
    struct msghdr * mp,       /* scatter-gather message header */
    int             flags     /* flags to underlying protocols */