1<?xml version="1.0" encoding="UTF-8" standalone="no"?> 2<!DOCTYPE html><html xmlns="http://www.w3.org/1999/xhtml"> 3 <head> 4 <title xmlns:xlink="http://www.w3.org/1999/xlink">eglQueryString - EGL Reference Pages</title> 5 <link rel="stylesheet" type="text/css" href="khronos-man.css"/> 6 <meta name="generator" content="DocBook XSL Stylesheets V1.79.1"/> 7 </head> 8 <body> 9 <header/> 10 <div class="refentry" id="eglQueryString"> 11 <div class="titlepage"/> 12 <div class="refnamediv"> 13 <h2>Name</h2> 14 <p>eglQueryString — 15 return a string describing properties of the EGL client or of an 16 <abbr class="acronym">EGL</abbr> display connection 17 </p> 18 </div> 19 <div class="refsynopsisdiv"> 20 <h2>C Specification</h2> 21 <div class="funcsynopsis"> 22 <table style="border: 0; cellspacing: 0; cellpadding: 0;" class="funcprototype-table"> 23 <tr> 24 <td> 25 <code class="funcdef">char const * <strong class="fsfunc">eglQueryString</strong>(</code> 26 </td> 27 <td>EGLDisplay <var class="pdparam">display</var>, </td> 28 </tr> 29 <tr> 30 <td> </td> 31 <td>EGLint <var class="pdparam">name</var><code>)</code>;</td> 32 </tr> 33 </table> 34 <div class="funcprototype-spacer"> </div> 35 </div> 36 </div> 37 <div class="refsect1" id="parameters"> 38 <h2>Parameters</h2> 39 <div class="variablelist"> 40 <dl class="variablelist"> 41 <dt> 42 <span class="term"> 43 <em class="parameter"> 44 <code>display</code> 45 </em> 46 </span> 47 </dt> 48 <dd> 49 <p> 50 Specifies the EGL display connection. 51 </p> 52 </dd> 53 <dt> 54 <span class="term"> 55 <em class="parameter"> 56 <code>name</code> 57 </em> 58 </span> 59 </dt> 60 <dd> 61 <p> 62 Specifies a symbolic constant, one of 63 <code class="constant">EGL_CLIENT_APIS</code>, 64 <code class="constant">EGL_VENDOR</code>, 65 <code class="constant">EGL_VERSION</code>, or 66 <code class="constant">EGL_EXTENSIONS</code>. 67 </p> 68 </dd> 69 </dl> 70 </div> 71 </div> 72 <div class="refsect1" id="description"> 73 <h2>Description</h2> 74 <p> 75 <code class="function">eglQueryString</code> returns a pointer to a 76 static, zero-terminated string describing properties of the EGL 77 client or of an EGL display connection. 78 <em class="parameter"><code>name</code></em> may be one of the following: 79 </p> 80 <div class="variablelist"> 81 <dl class="variablelist"> 82 <dt> 83 <span class="term"> 84 <code class="constant">EGL_CLIENT_APIS</code> 85 </span> 86 </dt> 87 <dd> 88 <p> 89 Returns a string describing which client rendering 90 APIs are supported. The string contains a 91 space-separated list of API names. The list must 92 include at least one of <code class="code">OpenGL</code>, 93 <code class="code">OpenGL_ES</code>, or <code class="code">OpenVG</code>. 94 These strings correspond respectively to values 95 <code class="constant">EGL_OPENGL_API</code>, 96 <code class="constant">EGL_OPENGL_ES_API</code>, and 97 <code class="constant">EGL_OPENVG_API</code> of the 98 <a class="citerefentry" href="eglBindAPI.xhtml"><span class="citerefentry"><span class="refentrytitle">eglBindAPI</span></span></a>, 99 <em class="parameter"><code>api</code></em> argument. 100 </p> 101 </dd> 102 <dt> 103 <span class="term"> 104 <code class="constant">EGL_VENDOR</code> 105 </span> 106 </dt> 107 <dd> 108 <p> 109 Returns the name of the vendor responsible for this EGL 110 implementation. The format and contents of the string 111 are implementation-dependent. 112 </p> 113 </dd> 114 <dt> 115 <span class="term"> 116 <code class="constant">EGL_VERSION</code> 117 </span> 118 </dt> 119 <dd> 120 <p> 121 Returns a version or release number. The 122 <code class="constant">EGL_VERSION</code> string is laid out 123 as follows: 124 </p> 125 <p> 126 <em class="replaceable"><code>major_version</code></em>.<em class="replaceable"><code>minor_version</code></em> 127 space 128 <em class="replaceable"><code>vendor_specific_info</code></em> 129 </p> 130 <p> 131 Both the major and minor portions of the version 132 number are numeric. Their values must match the 133 <em class="parameter"><code>major</code></em> and 134 <em class="parameter"><code>minor</code></em> values returned by 135 <a class="citerefentry" href="eglInitialize.xhtml"><span class="citerefentry"><span class="refentrytitle">eglInitialize</span></span></a>. 136 </p> 137 <p> 138 The vendor-specific information is optional; if 139 present, its format and contents are 140 implementation-specific. 141 </p> 142 </dd> 143 <dt> 144 <span class="term"> 145 <code class="constant">EGL_EXTENSIONS</code> 146 </span> 147 </dt> 148 <dd> 149 <p> 150 Returns a space separated list of supported 151 extensions to EGL. If there are no extensions, then 152 the empty string is returned. 153 </p> 154 <p> 155 If <em class="parameter"><code>display</code></em> is 156 <code class="constant">EGL_NO_DISPLAY</code>, then the 157 <code class="constant">EGL_EXTENSIONS</code> string describes 158 the set of supported <em class="firstterm">client 159 extensions</em>. If 160 <em class="parameter"><code>display</code></em> is a valid, 161 initialized display, then the 162 <code class="constant">EGL_EXTENSIONS</code> string describes 163 the set of <em class="firstterm">display extensions</em> 164 supported by that display. The set of supported 165 client extensions is disjoint from the set of 166 extensions supported by any given display. 167 </p> 168 </dd> 169 </dl> 170 </div> 171 </div> 172 <div class="refsect1" id="notes"> 173 <h2>Notes</h2> 174 <p> 175 <code class="constant">EGL_CLIENT_APIS</code> is supported only if 176 the EGL version is 1.2 or greater. 177 </p> 178 <p> 179 A <em class="parameter"><code>display</code></em> of 180 <code class="constant">EGL_NO_DISPLAY</code> is supported only if the EGL 181 version is 1.5 or greater. 182 </p> 183 </div> 184 <div class="refsect1" id="errors"> 185 <h2>Errors</h2> 186 <p> 187 <code class="constant">NULL</code> is returned on failure. 188 </p> 189 <p> 190 <code class="constant">EGL_BAD_DISPLAY</code> is generated if 191 <em class="parameter"><code>display</code></em> is not an EGL display connection, 192 unless <em class="parameter"><code>display</code></em> is 193 <code class="constant">EGL_NO_DISPLAY</code> and 194 <em class="parameter"><code>name</code></em> is 195 <code class="constant">EGL_EXTENSIONS</code>. 196 </p> 197 <p> 198 <code class="constant">EGL_NOT_INITIALIZED</code> is generated if 199 <em class="parameter"><code>display</code></em> is a valid but uninitialized 200 EGLDisplay. 201 </p> 202 <p> 203 <code class="constant">EGL_BAD_PARAMETER</code> is generated if 204 <em class="parameter"><code>name</code></em> is not an accepted value. 205 </p> 206 </div> 207 <div class="refsect1" id="seealso"> 208 <h2>See Also</h2> 209 <p> 210 <a class="citerefentry" href="eglBindAPI.xhtml"><span class="citerefentry"><span class="refentrytitle">eglBindAPI</span></span></a>, 211 <a class="citerefentry" href="eglGetDisplay.xhtml"><span class="citerefentry"><span class="refentrytitle">eglGetDisplay</span></span></a>, 212 <a class="citerefentry" href="eglInitialize.xhtml"><span class="citerefentry"><span class="refentrytitle">eglInitialize</span></span></a> 213 </p> 214 </div> 215 <p> 216 </p> 217 <div class="refsect3" id="copyright"> 218 <img src="KhronosLogo.jpg"/> 219 <p> 220 Copyright © 2003-2014 The Khronos Group Inc. 221 Permission is hereby granted, free of charge, to any person obtaining a 222 copy of this software and/or associated documentation files (the 223 "Materials"), to deal in the Materials without restriction, including 224 without limitation the rights to use, copy, modify, merge, publish, 225 distribute, sublicense, and/or sell copies of the Materials, and to 226 permit persons to whom the Materials are furnished to do so, subject to 227 the condition that this copyright notice and permission notice shall be included 228 in all copies or substantial portions of the Materials. 229 </p> 230 </div> 231 <p> 232</p> 233 </div> 234 <footer/> 235 </body> 236</html> 237
