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  24 <a href="#gnutls-extra.synopsis" class="shortcut">Top</a>
  25                    |
  26                   <a href="#gnutls-extra.description" class="shortcut">Description</a>
  27 </td></tr>
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  29 <div class="refentry">
  30 <a name="gnutls-extra"></a><div class="titlepage"></div>
  31 <div class="refnamediv"><table width="100%"><tr>
  32 <td valign="top">
  33 <h2><span class="refentrytitle"><a name="gnutls-extra.top_of_page"></a>extra</span></h2>
  34 <p>extra</p>
  35 </td>
  36 <td valign="top" align="right"></td>
  37 </tr></table></div>
  38 <div class="refsynopsisdiv">
  39 <a name="gnutls-extra.synopsis"></a><h2>Synopsis</h2>
  40 <pre class="synopsis">#define             <a class="link" href="gnutls-extra.html#GNUTLS-EXTRA-VERSION:CAPS" title="GNUTLS_EXTRA_VERSION">GNUTLS_EXTRA_VERSION</a>
  41 enum                <a class="link" href="gnutls-extra.html#gnutls-ia-apptype-t" title="enum gnutls_ia_apptype_t">gnutls_ia_apptype_t</a>;
  42 <a class="link" href="gnutls-crypto.html#int" title="int ()"><span class="returnvalue">int</span></a>                 (<a class="link" href="gnutls-extra.html#gnutls-ia-avp-func" title="gnutls_ia_avp_func ()">*gnutls_ia_avp_func</a>)               (<em class="parameter"><code><a class="link" href="gnutls-gnutls.html#gnutls-session-t" title="gnutls_session_t"><span class="type">gnutls_session_t</span></a> session</code></em>,
  43                                                          <em class="parameter"><code><span class="type">void</span> *ptr</code></em>,
  44                                                          <em class="parameter"><code>const <span class="type">char</span> *last</code></em>,
  45                                                          <em class="parameter"><code><span class="type">size_t</span> lastlen</code></em>,
  46                                                          <em class="parameter"><code><span class="type">char</span> **next</code></em>,
  47                                                          <em class="parameter"><code><span class="type">size_t</span> *nextlen</code></em>);
  48 <span class="returnvalue">void</span>                <a class="link" href="gnutls-extra.html#gnutls-ia-free-client-credentials" title="gnutls_ia_free_client_credentials ()">gnutls_ia_free_client_credentials</a>   ();
  49 <a class="link" href="gnutls-crypto.html#int" title="int ()"><span class="returnvalue">int</span></a>                 <a class="link" href="gnutls-extra.html#gnutls-ia-verify-endphase" title="gnutls_ia_verify_endphase ()">gnutls_ia_verify_endphase</a>           (<em class="parameter"><code><a class="link" href="gnutls-gnutls.html#gnutls-session-t" title="gnutls_session_t"><span class="type">gnutls_session_t</span></a> session</code></em>,
  50                                                          <em class="parameter"><code>const <span class="type">char</span> *checksum</code></em>);
  51 <span class="returnvalue">ssize_t</span>             <a class="link" href="gnutls-extra.html#gnutls-ia-send" title="gnutls_ia_send ()">gnutls_ia_send</a>                      (<em class="parameter"><code><a class="link" href="gnutls-gnutls.html#gnutls-session-t" title="gnutls_session_t"><span class="type">gnutls_session_t</span></a> session</code></em>,
  52                                                          <em class="parameter"><code>const <span class="type">char</span> *data</code></em>,
  53                                                          <em class="parameter"><code><span class="type">size_t</span> sizeofdata</code></em>);
  54 <span class="returnvalue">ssize_t</span>             <a class="link" href="gnutls-extra.html#gnutls-ia-recv" title="gnutls_ia_recv ()">gnutls_ia_recv</a>                      (<em class="parameter"><code><a class="link" href="gnutls-gnutls.html#gnutls-session-t" title="gnutls_session_t"><span class="type">gnutls_session_t</span></a> session</code></em>,
  55                                                          <em class="parameter"><code><span class="type">char</span> *data</code></em>,
  56                                                          <em class="parameter"><code><span class="type">size_t</span> sizeofdata</code></em>);
  57 <a class="link" href="gnutls-crypto.html#int" title="int ()"><span class="returnvalue">int</span></a>                 <a class="link" href="gnutls-extra.html#gnutls-ia-generate-challenge" title="gnutls_ia_generate_challenge ()">gnutls_ia_generate_challenge</a>        (<em class="parameter"><code><a class="link" href="gnutls-gnutls.html#gnutls-session-t" title="gnutls_session_t"><span class="type">gnutls_session_t</span></a> session</code></em>,
  58                                                          <em class="parameter"><code><span class="type">size_t</span> buffer_size</code></em>);
  59 <a class="link" href="gnutls-crypto.html#int" title="int ()"><span class="returnvalue">int</span></a>                 <a class="link" href="gnutls-extra.html#gnutls-register-md5-handler" title="gnutls_register_md5_handler ()">gnutls_register_md5_handler</a>         (<em class="parameter"><code><span class="type">void</span></code></em>);
  60 const <span class="returnvalue">char</span> *        <a class="link" href="gnutls-extra.html#gnutls-extra-check-version" title="gnutls_extra_check_version ()">gnutls_extra_check_version</a>          (<em class="parameter"><code>const <span class="type">char</span> *req_version</code></em>);
  61 </pre>
  62 </div>
  63 <div class="refsect1">
  64 <a name="gnutls-extra.description"></a><h2>Description</h2>
  65 <p>
  66 </p>
  67 </div>
  68 <div class="refsect1">
  69 <a name="gnutls-extra.details"></a><h2>Details</h2>
  70 <div class="refsect2">
  71 <a name="GNUTLS-EXTRA-VERSION:CAPS"></a><h3>GNUTLS_EXTRA_VERSION</h3>
  72 <pre class="programlisting">#define GNUTLS_EXTRA_VERSION GNUTLS_VERSION
  73 </pre>
  74 <p>
  75 </p>
  76 </div>
  77 <hr>
  78 <div class="refsect2">
  79 <a name="gnutls-ia-apptype-t"></a><h3>enum gnutls_ia_apptype_t</h3>
  80 <pre class="programlisting">typedef enum {
  81     GNUTLS_IA_APPLICATION_PAYLOAD = 0,
  82     GNUTLS_IA_INTERMEDIATE_PHASE_FINISHED = 1,
  83     GNUTLS_IA_FINAL_PHASE_FINISHED = 2
  84 } gnutls_ia_apptype_t;
  85 </pre>
  86 <p>
  87 Enumeration of different certificate encoding formats.
  88 </p>
  89 <div class="variablelist"><table border="0">
  90 <col align="left" valign="top">
  91 <tbody>
  92 <tr>
  93 <td><p><a name="GNUTLS-IA-APPLICATION-PAYLOAD:CAPS"></a><span class="term"><code class="literal">GNUTLS_IA_APPLICATION_PAYLOAD</code></span></p></td>
  94 <td>TLS/IA application payload.
  95 </td>
  96 </tr>
  97 <tr>
  98 <td><p><a name="GNUTLS-IA-INTERMEDIATE-PHASE-FINISHED:CAPS"></a><span class="term"><code class="literal">GNUTLS_IA_INTERMEDIATE_PHASE_FINISHED</code></span></p></td>
  99 <td>TLS/IA intermediate phase finished.
 100 </td>
 101 </tr>
 102 <tr>
 103 <td><p><a name="GNUTLS-IA-FINAL-PHASE-FINISHED:CAPS"></a><span class="term"><code class="literal">GNUTLS_IA_FINAL_PHASE_FINISHED</code></span></p></td>
 104 <td>TLS/IA final phase finished.
 105 </td>
 106 </tr>
 107 </tbody>
 108 </table></div>
 109 </div>
 110 <hr>
 111 <div class="refsect2">
 112 <a name="gnutls-ia-avp-func"></a><h3>gnutls_ia_avp_func ()</h3>
 113 <pre class="programlisting"><a class="link" href="gnutls-crypto.html#int" title="int ()"><span class="returnvalue">int</span></a>                 (*gnutls_ia_avp_func)               (<em class="parameter"><code><a class="link" href="gnutls-gnutls.html#gnutls-session-t" title="gnutls_session_t"><span class="type">gnutls_session_t</span></a> session</code></em>,
 114                                                          <em class="parameter"><code><span class="type">void</span> *ptr</code></em>,
 115                                                          <em class="parameter"><code>const <span class="type">char</span> *last</code></em>,
 116                                                          <em class="parameter"><code><span class="type">size_t</span> lastlen</code></em>,
 117                                                          <em class="parameter"><code><span class="type">char</span> **next</code></em>,
 118                                                          <em class="parameter"><code><span class="type">size_t</span> *nextlen</code></em>);</pre>
 119 <p>
 120 </p>
 121 </div>
 122 <hr>
 123 <div class="refsect2">
 124 <a name="gnutls-ia-free-client-credentials"></a><h3>gnutls_ia_free_client_credentials ()</h3>
 125 <pre class="programlisting"><span class="returnvalue">void</span>                gnutls_ia_free_client_credentials   ();</pre>
 126 <p>
 127 This structure is complex enough to manipulate directly thus this
 128 helper function is provided in order to free (deallocate) it.
 129 </p>
 130 <div class="variablelist"><table border="0">
 131 <col align="left" valign="top">
 132 <tbody><tr>
 133 <td><p><span class="term"><em class="parameter"><code>sc</code></em> :</span></p></td>
 134 <td>is a <span class="type">gnutls_ia_client_credentials_t</span> structure.</td>
 135 </tr></tbody>
 136 </table></div>
 137 </div>
 138 <hr>
 139 <div class="refsect2">
 140 <a name="gnutls-ia-verify-endphase"></a><h3>gnutls_ia_verify_endphase ()</h3>
 141 <pre class="programlisting"><a class="link" href="gnutls-crypto.html#int" title="int ()"><span class="returnvalue">int</span></a>                 gnutls_ia_verify_endphase           (<em class="parameter"><code><a class="link" href="gnutls-gnutls.html#gnutls-session-t" title="gnutls_session_t"><span class="type">gnutls_session_t</span></a> session</code></em>,
 142                                                          <em class="parameter"><code>const <span class="type">char</span> *checksum</code></em>);</pre>
 143 <p>
 144 Verify TLS/IA end phase checksum data.  If verification fails, the
 145 <a class="link" href="gnutls-gnutls.html#GNUTLS-A-INNER-APPLICATION-VERIFICATION:CAPS"><code class="literal">GNUTLS_A_INNER_APPLICATION_VERIFICATION</code></a> alert is sent to the other
 146 sie.
 147 </p>
 148 <p>
 149 This function is called when <a class="link" href="gnutls-extra.html#gnutls-ia-recv" title="gnutls_ia_recv ()"><code class="function">gnutls_ia_recv()</code></a> return
 150 <a class="link" href="gnutls-gnutls.html#GNUTLS-E-WARNING-IA-IPHF-RECEIVED:CAPS" title="GNUTLS_E_WARNING_IA_IPHF_RECEIVED"><code class="literal">GNUTLS_E_WARNING_IA_IPHF_RECEIVED</code></a> or
 151 <a class="link" href="gnutls-gnutls.html#GNUTLS-E-WARNING-IA-FPHF-RECEIVED:CAPS" title="GNUTLS_E_WARNING_IA_FPHF_RECEIVED"><code class="literal">GNUTLS_E_WARNING_IA_FPHF_RECEIVED</code></a>.
 152 </p>
 153 <div class="variablelist"><table border="0">
 154 <col align="left" valign="top">
 155 <tbody>
 156 <tr>
 157 <td><p><span class="term"><em class="parameter"><code>session</code></em> :</span></p></td>
 158 <td>is a <a class="link" href="gnutls-gnutls.html#gnutls-session-t" title="gnutls_session_t"><span class="type">gnutls_session_t</span></a> structure.</td>
 159 </tr>
 160 <tr>
 161 <td><p><span class="term"><em class="parameter"><code>checksum</code></em> :</span></p></td>
 162 <td>12-byte checksum data, received from <a class="link" href="gnutls-extra.html#gnutls-ia-recv" title="gnutls_ia_recv ()"><code class="function">gnutls_ia_recv()</code></a>.</td>
 163 </tr>
 164 <tr>
 165 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 166 <td>Return 0 on successful verification, or an error
 167 code.  If the checksum verification of the end phase message fails,
 168 <a class="link" href="gnutls-gnutls.html#GNUTLS-E-IA-VERIFY-FAILED:CAPS" title="GNUTLS_E_IA_VERIFY_FAILED"><code class="literal">GNUTLS_E_IA_VERIFY_FAILED</code></a> is returned.</td>
 169 </tr>
 170 </tbody>
 171 </table></div>
 172 </div>
 173 <hr>
 174 <div class="refsect2">
 175 <a name="gnutls-ia-send"></a><h3>gnutls_ia_send ()</h3>
 176 <pre class="programlisting"><span class="returnvalue">ssize_t</span>             gnutls_ia_send                      (<em class="parameter"><code><a class="link" href="gnutls-gnutls.html#gnutls-session-t" title="gnutls_session_t"><span class="type">gnutls_session_t</span></a> session</code></em>,
 177                                                          <em class="parameter"><code>const <span class="type">char</span> *data</code></em>,
 178                                                          <em class="parameter"><code><span class="type">size_t</span> sizeofdata</code></em>);</pre>
 179 <p>
 180 Send TLS/IA application payload data.  This function has the
 181 similar semantics with <code class="function">send()</code>.  The only difference is that it
 182 accepts a GnuTLS session, and uses different error codes.
 183 </p>
 184 <p>
 185 The TLS/IA protocol is synchronous, so you cannot send more than
 186 one packet at a time.  The client always send the first packet.
 187 </p>
 188 <p>
 189 To finish an application phase in the server, use
 190 <code class="function">gnutls_ia_endphase_send()</code>.  The client cannot end an application
 191 phase unilaterally; rather, a client is required to respond with an
 192 endphase of its own if gnutls_ia_recv indicates that the server has
 193 sent one.
 194 </p>
 195 <p>
 196 If the EINTR is returned by the internal push function (the default
 197 is <code class="function">send()</code>} then <a class="link" href="gnutls-gnutls.html#GNUTLS-E-INTERRUPTED:CAPS" title="GNUTLS_E_INTERRUPTED"><code class="literal">GNUTLS_E_INTERRUPTED</code></a> will be returned.  If
 198 <a class="link" href="gnutls-gnutls.html#GNUTLS-E-INTERRUPTED:CAPS" title="GNUTLS_E_INTERRUPTED"><code class="literal">GNUTLS_E_INTERRUPTED</code></a> or <a class="link" href="gnutls-gnutls.html#GNUTLS-E-AGAIN:CAPS" title="GNUTLS_E_AGAIN"><code class="literal">GNUTLS_E_AGAIN</code></a> is returned, you must call
 199 this function again, with the same parameters; alternatively you
 200 could provide a <a href="http://library.gnome.org/devel/glib/unstable/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a> pointer for data, and 0 for size.
 201 </p>
 202 <div class="variablelist"><table border="0">
 203 <col align="left" valign="top">
 204 <tbody>
 205 <tr>
 206 <td><p><span class="term"><em class="parameter"><code>session</code></em> :</span></p></td>
 207 <td>is a <a class="link" href="gnutls-gnutls.html#gnutls-session-t" title="gnutls_session_t"><span class="type">gnutls_session_t</span></a> structure.</td>
 208 </tr>
 209 <tr>
 210 <td><p><span class="term"><em class="parameter"><code>data</code></em> :</span></p></td>
 211 <td>contains the data to send</td>
 212 </tr>
 213 <tr>
 214 <td><p><span class="term"><em class="parameter"><code>sizeofdata</code></em> :</span></p></td>
 215 <td>is the length of the data</td>
 216 </tr>
 217 <tr>
 218 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 219 <td>The number of bytes sent, or a negative error code.</td>
 220 </tr>
 221 </tbody>
 222 </table></div>
 223 </div>
 224 <hr>
 225 <div class="refsect2">
 226 <a name="gnutls-ia-recv"></a><h3>gnutls_ia_recv ()</h3>
 227 <pre class="programlisting"><span class="returnvalue">ssize_t</span>             gnutls_ia_recv                      (<em class="parameter"><code><a class="link" href="gnutls-gnutls.html#gnutls-session-t" title="gnutls_session_t"><span class="type">gnutls_session_t</span></a> session</code></em>,
 228                                                          <em class="parameter"><code><span class="type">char</span> *data</code></em>,
 229                                                          <em class="parameter"><code><span class="type">size_t</span> sizeofdata</code></em>);</pre>
 230 <p>
 231 Receive TLS/IA data.  This function has the similar semantics with
 232 <code class="function">recv()</code>.  The only difference is that it accepts a GnuTLS session,
 233 and uses different error codes.
 234 </p>
 235 <p>
 236 If the server attempt to finish an application phase, this function
 237 will return <a class="link" href="gnutls-gnutls.html#GNUTLS-E-WARNING-IA-IPHF-RECEIVED:CAPS" title="GNUTLS_E_WARNING_IA_IPHF_RECEIVED"><code class="literal">GNUTLS_E_WARNING_IA_IPHF_RECEIVED</code></a> or
 238 <a class="link" href="gnutls-gnutls.html#GNUTLS-E-WARNING-IA-FPHF-RECEIVED:CAPS" title="GNUTLS_E_WARNING_IA_FPHF_RECEIVED"><code class="literal">GNUTLS_E_WARNING_IA_FPHF_RECEIVED</code></a>.  The caller should then invoke
 239 <a class="link" href="gnutls-extra.html#gnutls-ia-verify-endphase" title="gnutls_ia_verify_endphase ()"><code class="function">gnutls_ia_verify_endphase()</code></a>, and if it runs the client side, also
 240 send an endphase message of its own using gnutls_ia_endphase_send.
 241 </p>
 242 <p>
 243 If EINTR is returned by the internal push function (the default is
 244 <em class="parameter"><code>code</code></em>{<code class="function">recv()</code>}) then GNUTLS_E_INTERRUPTED will be returned.  If
 245 GNUTLS_E_INTERRUPTED or GNUTLS_E_AGAIN is returned, you must call
 246 this function again, with the same parameters; alternatively you
 247 could provide a NULL pointer for data, and 0 for size.
 248 </p>
 249 <div class="variablelist"><table border="0">
 250 <col align="left" valign="top">
 251 <tbody>
 252 <tr>
 253 <td><p><span class="term"><em class="parameter"><code>session</code></em> :</span></p></td>
 254 <td>is a <a class="link" href="gnutls-gnutls.html#gnutls-session-t" title="gnutls_session_t"><span class="type">gnutls_session_t</span></a> structure.</td>
 255 </tr>
 256 <tr>
 257 <td><p><span class="term"><em class="parameter"><code>data</code></em> :</span></p></td>
 258 <td>the buffer that the data will be read into, must hold &gt;= 12 bytes.</td>
 259 </tr>
 260 <tr>
 261 <td><p><span class="term"><em class="parameter"><code>sizeofdata</code></em> :</span></p></td>
 262 <td>the number of requested bytes, must be &gt;= 12.</td>
 263 </tr>
 264 <tr>
 265 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 266 <td>The number of bytes received.  A negative error code is
 267 returned in case of an error.  The
 268 <a class="link" href="gnutls-gnutls.html#GNUTLS-E-WARNING-IA-IPHF-RECEIVED:CAPS" title="GNUTLS_E_WARNING_IA_IPHF_RECEIVED"><code class="literal">GNUTLS_E_WARNING_IA_IPHF_RECEIVED</code></a> and
 269 <a class="link" href="gnutls-gnutls.html#GNUTLS-E-WARNING-IA-FPHF-RECEIVED:CAPS" title="GNUTLS_E_WARNING_IA_FPHF_RECEIVED"><code class="literal">GNUTLS_E_WARNING_IA_FPHF_RECEIVED</code></a> errors are returned when an
 270 application phase finished message has been sent by the server.</td>
 271 </tr>
 272 </tbody>
 273 </table></div>
 274 </div>
 275 <hr>
 276 <div class="refsect2">
 277 <a name="gnutls-ia-generate-challenge"></a><h3>gnutls_ia_generate_challenge ()</h3>
 278 <pre class="programlisting"><a class="link" href="gnutls-crypto.html#int" title="int ()"><span class="returnvalue">int</span></a>                 gnutls_ia_generate_challenge        (<em class="parameter"><code><a class="link" href="gnutls-gnutls.html#gnutls-session-t" title="gnutls_session_t"><span class="type">gnutls_session_t</span></a> session</code></em>,
 279                                                          <em class="parameter"><code><span class="type">size_t</span> buffer_size</code></em>);</pre>
 280 <p>
 281 Generate an application challenge that the client cannot control or
 282 predict, based on the TLS/IA inner secret.
 283 </p>
 284 <div class="variablelist"><table border="0">
 285 <col align="left" valign="top">
 286 <tbody>
 287 <tr>
 288 <td><p><span class="term"><em class="parameter"><code>session</code></em> :</span></p></td>
 289 <td>is a <a class="link" href="gnutls-gnutls.html#gnutls-session-t" title="gnutls_session_t"><span class="type">gnutls_session_t</span></a> structure.</td>
 290 </tr>
 291 <tr>
 292 <td><p><span class="term"><em class="parameter"><code>buffer_size</code></em> :</span></p></td>
 293 <td>size of output buffer.</td>
 294 </tr>
 295 <tr>
 296 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 297 <td>Returns 0 on success, or an negative error code.</td>
 298 </tr>
 299 </tbody>
 300 </table></div>
 301 </div>
 302 <hr>
 303 <div class="refsect2">
 304 <a name="gnutls-register-md5-handler"></a><h3>gnutls_register_md5_handler ()</h3>
 305 <pre class="programlisting"><a class="link" href="gnutls-crypto.html#int" title="int ()"><span class="returnvalue">int</span></a>                 gnutls_register_md5_handler         (<em class="parameter"><code><span class="type">void</span></code></em>);</pre>
 306 <p>
 307 Register a non-libgcrypt based MD5 and HMAC-MD5 handler.  This is
 308 useful if you run Libgcrypt in FIPS-mode.  Normally TLS requires
 309 use of MD5, so without this you cannot use GnuTLS with libgcrypt in
 310 FIPS mode.
 311 </p>
 312 <div class="variablelist"><table border="0">
 313 <col align="left" valign="top">
 314 <tbody><tr>
 315 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 316 <td>
 317 <a class="link" href="gnutls-gnutls.html#GNUTLS-E-SUCCESS:CAPS" title="GNUTLS_E_SUCCESS"><code class="literal">GNUTLS_E_SUCCESS</code></a> on success, otherwise an error.</td>
 318 </tr></tbody>
 319 </table></div>
 320 <p class="since">Since 2.6.0</p>
 321 </div>
 322 <hr>
 323 <div class="refsect2">
 324 <a name="gnutls-extra-check-version"></a><h3>gnutls_extra_check_version ()</h3>
 325 <pre class="programlisting">const <span class="returnvalue">char</span> *        gnutls_extra_check_version          (<em class="parameter"><code>const <span class="type">char</span> *req_version</code></em>);</pre>
 326 <p>
 327 Check GnuTLS Extra Library version.
 328 </p>
 329 <p>
 330 See <a class="link" href="gnutls-extra.html#GNUTLS-EXTRA-VERSION:CAPS" title="GNUTLS_EXTRA_VERSION"><code class="literal">GNUTLS_EXTRA_VERSION</code></a> for a suitable <em class="parameter"><code>req_version</code></em> string.
 331 </p>
 332 <div class="variablelist"><table border="0">
 333 <col align="left" valign="top">
 334 <tbody>
 335 <tr>
 336 <td><p><span class="term"><em class="parameter"><code>req_version</code></em> :</span></p></td>
 337 <td>version string to compare with, or <a href="http://library.gnome.org/devel/glib/unstable/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a>.</td>
 338 </tr>
 339 <tr>
 340 <td><p><span class="term"><span class="emphasis"><em>Returns</em></span> :</span></p></td>
 341 <td>Check that the version of the library is at
 342 minimum the one given as a string in <em class="parameter"><code>req_version</code></em> and return the
 343 actual version string of the library; return <a href="http://library.gnome.org/devel/glib/unstable/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a> if the
 344 condition is not met.  If <a href="http://library.gnome.org/devel/glib/unstable/glib-Standard-Macros.html#NULL:CAPS"><code class="literal">NULL</code></a> is passed to this function no
 345 check is done and only the version string is returned.</td>
 346 </tr>
 347 </tbody>
 348 </table></div>
 349 </div>
 350 </div>
 351 </div>
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