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<li> - 1 - error in processing <li> 0 - DNS reply successfully processed </ul>
</dl><dl compact><dt><b>Note: </b></dt><dd>
 <ul>
<li> Event listeners are NOT to be invoked directly. They are callback functions invoked by the TCP/IP stack to notify events.</ul>
</dl>This, of course, is where responses from DNS server are processed and checked whether they contain the IP address we requested or if they contain authorative name server to which we should proceed.
<p>
If we received the IP address we requested, <a class="el" href="dns_8h.html#a5">DNS_EVENT_SUCCESS</a> is reported to application DNS event listener. Otherwise <a class="el" href="dns_8h.html#a4">DNS_EVENT_ERROR</a> is reported. 
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Definition at line <a class="el" href="dns_8c-source.html#l00205">205</a> of file <a class="el" href="dns_8c-source.html">dns.c</a>.
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References <a class="el" href="dns_8h-source.html#l00124">DNS_ERROR_GENERAL</a>, <a class="el" href="dns_8h-source.html#l00084">DNS_EVENT_ERROR</a>, <a class="el" href="dns_8h-source.html#l00087">DNS_EVENT_SUCCESS</a>, <a class="el" href="dns_8c-source.html#l00095">dns_hostptr</a>, <a class="el" href="dns_8c-source.html#l00142">dns_retransmit()</a>, <a class="el" href="dns_8c-source.html#l00089">dns_socket</a>, <a class="el" href="dns_8c-source.html#l00088">dns_state</a>, <a class="el" href="dns_8c-source.html#l00093">dns_tmp_ip</a>, <a class="el" href="system_8h-source.html#l00210">RECEIVE_NETWORK_B</a>, and <a class="el" href="tcp__ip_8h-source.html#l00276">UDP_EVENT_DATA</a>.
<p>
Referenced by <a class="el" href="dns_8c-source.html#l00108">dns_init()</a>.    </td>
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<a name="a14" doxytag="dns.c::get_host_by_name"></a><p>
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          <td class="md" nowrap valign="top"> UINT8 get_host_by_name </td>
          <td class="md" valign="top">(&nbsp;</td>
          <td class="md" nowrap valign="top">UINT8 *&nbsp;</td>
          <td class="mdname" nowrap>&nbsp; <em>host_name_ptr</em>, </td>
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          <td class="md" nowrap>void(*&nbsp;</td>
          <td class="mdname" nowrap>&nbsp; <em>listener</em>)(UINT8, UINT32)</td>
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          <td class="md">)&nbsp;</td>
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<p>
<dl compact><dt><b>Author: </b></dt><dd>
 <ul>
<li> Vladan Jovanovic (<a href="mailto:[e-mail]">[e-mail]</a>) </ul>
</dl><dl compact><dt><b>Date: </b></dt><dd>
10.10.2002 </dl><dl compact><dt><b>Parameters: </b></dt><dd>
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<tr><td valign=top><em>host_name_ptr</em>&nbsp;</td><td>
Pointer to null-terminated host name to be resolved </td></tr>
<tr><td valign=top><em>listener</em>&nbsp;</td><td>
Pointer to DNS listener function that listens to events from DNS client. This function takes two parameters: first one can take a value of <a class="el" href="dns_8h.html#a5">DNS_EVENT_SUCCESS</a> or <a class="el" href="dns_8h.html#a4">DNS_EVENT_ERROR</a> and thus determine the meaning of the second parameter. If first parameter is <a class="el" href="dns_8h.html#a5">DNS_EVENT_SUCCESS</a>, second parameter represents requested IP address. In case of <a class="el" href="dns_8h.html#a4">DNS_EVENT_ERROR</a>, second parameter can be one of the: <a class="el" href="dns_8h.html#a6">DNS_ERROR_FORMAT</a>, <a class="el" href="dns_8h.html#a7">DNS_ERROR_SERVER_FAILURE</a>, <a class="el" href="dns_8h.html#a8">DNS_ERROR_NAME_ERROR</a>, <a class="el" href="dns_8h.html#a9">DNS_ERROR_NOT_IMPLEMENTED</a>, <a class="el" href="dns_8h.html#a10">DNS_ERROR_REFUSED</a>, <a class="el" href="dns_8h.html#a11">DNS_ERROR_TIMEOUT</a>, <a class="el" href="dns_8h.html#a12">DNS_ERROR_GENERAL</a> </td></tr>
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</dl><dl compact><dt><b>Returns: </b></dt><dd>
 <ul>
<li> <a class="el" href="dns_8h.html#a13">DNS_ERROR_BUSY</a> - Signals that DNS is currently processing another request so it is not possible to process a new one <li> <a class="el" href="dns_8h.html#a16">DNS_ERROR_OVERFLOW</a> - Network transmit buffer too small to hold DNS request <li> <a class="el" href="dns_8h.html#a14">DNS_ERROR_LABEL</a> - Label in host name longer than 63 bytes. Error <li> <a class="el" href="dns_8h.html#a15">DNS_ERROR_NAME</a> - Host name longer than 264 bytes. Error</ul>
</dl>Invoke this function to start name-resolving process. Note that currently DNS client can process only one request at a time and will not allow multiple requests. 
<p>
Definition at line <a class="el" href="dns_8c-source.html#l00445">445</a> of file <a class="el" href="dns_8c-source.html">dns.c</a>.
<p>
References <a class="el" href="dns_8h-source.html#l00135">DNS_ERROR_BUSY</a>, <a class="el" href="dns_8c-source.html#l00095">dns_hostptr</a>, <a class="el" href="dns_8h-source.html#l00078">DNS_NUM_RETRIES</a>, <a class="el" href="dns_8h-source.html#l00075">DNS_RESEND_PERIOD</a>, <a class="el" href="dns_8c-source.html#l00091">dns_retries</a>, <a class="el" href="dns_8h-source.html#l00073">DNS_SERVER_IP</a>, <a class="el" href="dns_8c-source.html#l00089">dns_socket</a>, <a class="el" href="dns_8c-source.html#l00088">dns_state</a>, <a class="el" href="dns_8c-source.html#l00090">dns_timer</a>, <a class="el" href="dns_8c-source.html#l00093">dns_tmp_ip</a>, <a class="el" href="dns_8h-source.html#l00069">DNS_UDP_PORT</a>, <a class="el" href="timers_8c-source.html#l00194">init_timer()</a>, <a class="el" href="system_8h-source.html#l00091">NETWORK_TX_BUFFER_SIZE</a>, <a class="el" href="system_8h-source.html#l00163">RESET_SYSTEM</a>, <a class="el" href="timers_8h-source.html#l00086">TIMERTIC</a>, <a class="el" href="tcp__ip_8h-source.html#l00471">UDP_APP_OFFSET</a>, and <a class="el" href="udp_8c-source.html#l00395">udp_send()</a>.
<p>
Referenced by <a class="el" href="dns_8c-source.html#l00142">dns_retransmit()</a>.    </td>
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<hr><h2>Variable Documentation</h2>
<a name="a3" doxytag="dns.c::dns_state"></a><p>
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          <td class="md" nowrap valign="top"> UINT8 dns_state
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Current DNS state. Used to prevent multiple requests, issue retransmissions,... See DNS_STATE_* for possible values. 
<p>
Definition at line <a class="el" href="dns_8c-source.html#l00088">88</a> of file <a class="el" href="dns_8c-source.html">dns.c</a>.
<p>
Referenced by <a class="el" href="dns_8c-source.html#l00205">dns_eventlistener()</a>, <a class="el" href="dns_8c-source.html#l00108">dns_init()</a>, <a class="el" href="dns_8c-source.html#l00142">dns_retransmit()</a>, <a class="el" href="dns_8c-source.html#l00168">dns_run()</a>, and <a class="el" href="dns_8c-source.html#l00445">get_host_by_name()</a>.    </td>
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<a name="a4" doxytag="dns.c::dns_socket"></a><p>
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          <td class="md" nowrap valign="top"> UINT8 dns_socket
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<p>
UDP socket used by the DNS resolver 
<p>
Definition at line <a class="el" href="dns_8c-source.html#l00089">89</a> of file <a class="el" href="dns_8c-source.html">dns.c</a>.
<p>
Referenced by <a class="el" href="dns_8c-source.html#l00205">dns_eventlistener()</a>, <a class="el" href="dns_8c-source.html#l00108">dns_init()</a>, and <a class="el" href="dns_8c-source.html#l00445">get_host_by_name()</a>.    </td>
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<a name="a5" doxytag="dns.c::dns_timer"></a><p>
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          <td class="md" nowrap valign="top"> UINT8 dns_timer
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<p>
DNS timer handle used for retransmissions 
<p>
Definition at line <a class="el" href="dns_8c-source.html#l00090">90</a> of file <a class="el" href="dns_8c-source.html">dns.c</a>.
<p>
Referenced by <a class="el" href="dns_8c-source.html#l00108">dns_init()</a>, <a class="el" href="dns_8c-source.html#l00142">dns_retransmit()</a>, <a class="el" href="dns_8c-source.html#l00168">dns_run()</a>, and <a class="el" href="dns_8c-source.html#l00445">get_host_by_name()</a>.    </td>
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<a name="a6" doxytag="dns.c::dns_retries"></a><p>
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          <td class="md" nowrap valign="top"> UINT8 dns_retries
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<p>
DNS retry counter used for detecting timeouts 
<p>
Definition at line <a class="el" href="dns_8c-source.html#l00091">91</a> of file <a class="el" href="dns_8c-source.html">dns.c</a>.
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Referenced by <a class="el" href="dns_8c-source.html#l00142">dns_retransmit()</a>, and <a class="el" href="dns_8c-source.html#l00445">get_host_by_name()</a>.    </td>
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<a name="a7" doxytag="dns.c::dns_tmp_ip"></a><p>
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          <td class="md" nowrap valign="top"> UINT32 dns_tmp_ip
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<p>
Used in many ways: as an IP address holder, for issuing requests to authorative name servers,.. 
<p>
Definition at line <a class="el" href="dns_8c-source.html#l00093">93</a> of file <a class="el" href="dns_8c-source.html">dns.c</a>.
<p>
Referenced by <a class="el" href="dns_8c-source.html#l00205">dns_eventlistener()</a>, and <a class="el" href="dns_8c-source.html#l00445">get_host_by_name()</a>.    </td>
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<a name="a8" doxytag="dns.c::dns_hostptr"></a><p>
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          <td class="md" nowrap valign="top"> UINT8* dns_hostptr
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<p>
Pointer to hostname that is beeing resolved. Needed for retransmissions. 
<p>
Definition at line <a class="el" href="dns_8c-source.html#l00095">95</a> of file <a class="el" href="dns_8c-source.html">dns.c</a>.
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Referenced by <a class="el" href="dns_8c-source.html#l00205">dns_eventlistener()</a>, <a class="el" href="dns_8c-source.html#l00142">dns_retransmit()</a>, and <a class="el" href="dns_8c-source.html#l00445">get_host_by_name()</a>.    </td>
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