1<root> 2<function name="gst_plugin_load_file"> 3<description> 4Loads a plugin from file. 5</description> 6<parameters> 7<parameter name="filename"> 8<parameter_description> the plugin filename to load 9</parameter_description> 10</parameter> 11<parameter name="error"> 12<parameter_description> pointer to a NULL-valued GError 13</parameter_description> 14</parameter> 15</parameters> 16<return> a reference to the existing loaded GstPlugin, a reference to the 17newly-loaded GstPlugin, or NULL if an error occurred. 18</return> 19</function> 20 21<function name="gst_element_factory_make"> 22<description> 23Create a new element of the type defined by the given element factory. 24 25 26</description> 27<parameters> 28<parameter name="factoryname"> 29<parameter_description> a named factory to instantiate 30</parameter_description> 31</parameter> 32<parameter name="name"> 33<parameter_description> name of new element 34</parameter_description> 35</parameter> 36</parameters> 37<return> new #GstElement or NULL if unable to create element 38</return> 39</function> 40 41<function name="gst_query_type_iterate_definitions"> 42<description> 43Get a #GstIteratorBasic of all the registered query types. The definitions 44iterated over are read only. 45 46 47</description> 48<parameters> 49</parameters> 50<return> A #GstIteratorBasic of #GstQueryTypeDefinition. 51</return> 52</function> 53 54<function name="gst_clock_id_wait"> 55<description> 56Perform a blocking wait on the Gst::ClockID. 57The Gst::ClockID should have been created with 58Gst::Clock::create_single_shot_id() or Gst::Clock::create_periodic_id() 59and should not have been unscheduled with a call to unschedule(). 60 61If this function returns #GST_CLOCK_OK or #GST_CLOCK_EARLY, 62the @jitter argument will contain the difference 63against the clock and the time of the Gst::ClockID when this method was 64called. 65Positive values indicate how late the Gst::ClockID was relative to the clock 66(in which case this function will return #GST_CLOCK_EARLY). 67Negative values indicate how much time was spent waiting on the clock 68before this function returned. 69 70 71</description> 72<parameters> 73<parameter name="id"> 74<parameter_description> The #GstClockID to wait on 75</parameter_description> 76</parameter> 77<parameter name="jitter"> 78<parameter_description> A pointer that will contain the jitter. 79</parameter_description> 80</parameter> 81</parameters> 82<return> the result of the blocking wait. #GST_CLOCK_EARLY will be returned 83if the current clock time is past the time of the Gst::ClockID, #GST_CLOCK_OK 84if Gst::ClockID was scheduled in time. #GST_CLOCK_UNSCHEDULED if Gst::ClockID 85was unscheduled with unschedule(). 86 87MT safe. 88</return> 89</function> 90 91<function name="gst_type_find_peek"> 92<description> 93Returns the @size bytes of the stream to identify beginning at offset. If 94offset is a positive number, the offset is relative to the beginning of the 95stream, if offset is a negative number the offset is relative to the end of 96the stream. The returned memory is valid until the typefinding function 97returns and must not be freed. 98 99Returns: the requested data, or NULL if that data is not available. 100 101</description> 102<parameters> 103<parameter name="find"> 104<parameter_description> The #GstTypeFind object the function was called with 105</parameter_description> 106</parameter> 107<parameter name="offset"> 108<parameter_description> The offset 109</parameter_description> 110</parameter> 111<parameter name="size"> 112<parameter_description> The number of bytes to return 113</parameter_description> 114</parameter> 115</parameters> 116<return> the requested data, or NULL if that data is not available. 117</return> 118</function> 119 120<function name="gst_type_find_suggest"> 121<description> 122If a Gst::TypeFind::SlotFind calls this method it suggests the caps with the 123given probability. A Gst::TypeFind::SlotFind may supply different suggestions 124in one call. 125It is up to the caller of the Gst::TypeFind::SlotFind to interpret these 126values. 127 128</description> 129<parameters> 130<parameter name="find"> 131<parameter_description> The #GstTypeFind object the function was called with 132</parameter_description> 133</parameter> 134<parameter name="probability"> 135<parameter_description> The probability in percent that the suggestion is right 136</parameter_description> 137</parameter> 138<parameter name="caps"> 139<parameter_description> The fixed #GstCaps to suggest 140</parameter_description> 141</parameter> 142</parameters> 143<return></return> 144</function> 145 146<function name="gst_type_find_factory_call_function"> 147<description> 148Calls the Gst::TypeFind::SlotFind associated with this factory. 149 150</description> 151<parameters> 152<parameter name="factory"> 153<parameter_description> A #GstTypeFindFactory 154</parameter_description> 155</parameter> 156<parameter name="find"> 157<parameter_description> A properly setup #GstTypeFind entry. The get_data and suggest_type 158members must be set. 159</parameter_description> 160</parameter> 161</parameters> 162<return></return> 163</function> 164 165<function name="gst_bus_poll"> 166<description> 167Poll the bus for messages. Will block while waiting for messages to come. 168You can specify a maximum time to poll with the @timeout parameter. If 169@timeout is negative, this function will block indefinitely. 170 171All messages not in @events will be popped off the bus and will be ignored. 172It is not possible to use message enums beyond #GST_MESSAGE_EXTENDED in the 173@events mask 174 175Because poll is implemented using the "message" signal enabled by 176gst_bus_add_signal_watch(), calling gst_bus_poll() will cause the "message" 177signal to be emitted for every message that poll sees. Thus a "message" 178signal handler will see the same messages that this function sees -- neither 179will steal messages from the other. 180 181This function will run a main loop from the default main context when 182polling. 183 184You should never use this function, since it is pure evil. This is 185especially true for GUI applications based on Gtk+ or Qt, but also for any 186other non-trivial application that uses the GLib main loop. As this function 187runs a GLib main loop, any callback attached to the default GLib main 188context may be invoked. This could be timeouts, GUI events, I/O events etc.; 189even if gst_bus_poll() is called with a 0 timeout. Any of these callbacks 190may do things you do not expect, e.g. destroy the main application window or 191some other resource; change other application state; display a dialog and 192run another main loop until the user clicks it away. In short, using this 193function may add a lot of complexity to your code through unexpected 194re-entrancy and unexpected changes to your application's state. 195 196For 0 timeouts use gst_bus_pop_filtered() instead of this function; for 197other short timeouts use gst_bus_timed_pop_filtered(); everything else is 198better handled by setting up an asynchronous bus watch and doing things 199from there. 200 201 202</description> 203<parameters> 204<parameter name="bus"> 205<parameter_description> a #GstBus 206</parameter_description> 207</parameter> 208<parameter name="events"> 209<parameter_description> a mask of #GstMessageType, representing the set of message types to 210poll for (note special handling of extended message types below) 211</parameter_description> 212</parameter> 213<parameter name="timeout"> 214<parameter_description> the poll timeout, as a #GstClockTime, or #GST_CLOCK_TIME_NONE to poll 215indefinitely. 216</parameter_description> 217</parameter> 218</parameters> 219<return> the message that was received, 220or %NULL if the poll timed out. The message is taken from the 221bus. 222</return> 223</function> 224 225<function name="gst_bus_pop"> 226<description> 227Get a message from the bus. 228 229 230</description> 231<parameters> 232<parameter name="bus"> 233<parameter_description> a #GstBus to pop 234</parameter_description> 235</parameter> 236</parameters> 237<return> the #GstMessage that is on the 238bus, or %NULL if the bus is empty. The message is taken from 239the bus. 240 241MT safe. 242</return> 243</function> 244 245<function name="gst_bus_pop_filtered"> 246<description> 247Get a message matching @type from the bus. Will discard all messages on 248the bus that do not match @type and that have been posted before the first 249message that does match @type. If there is no message matching @type on 250the bus, all messages will be discarded. It is not possible to use message 251enums beyond #GST_MESSAGE_EXTENDED in the @events mask. 252 253 254</description> 255<parameters> 256<parameter name="bus"> 257<parameter_description> a #GstBus to pop 258</parameter_description> 259</parameter> 260<parameter name="types"> 261<parameter_description> message types to take into account 262</parameter_description> 263</parameter> 264</parameters> 265<return> the next #GstMessage matching 266@type that is on the bus, or %NULL if the bus is empty or there 267is no message matching @type. The message is taken from the bus. 268 269MT safe. 270</return> 271</function> 272 273<function name="gst_bus_timed_pop"> 274<description> 275Get a message from the bus, waiting up to the specified timeout. 276 277If @timeout is 0, this function behaves like gst_bus_pop(). If @timeout is 278#GST_CLOCK_TIME_NONE, this function will block forever until a message was 279posted on the bus. 280 281 282</description> 283<parameters> 284<parameter name="bus"> 285<parameter_description> a #GstBus to pop 286</parameter_description> 287</parameter> 288<parameter name="timeout"> 289<parameter_description> a timeout 290</parameter_description> 291</parameter> 292</parameters> 293<return> the #GstMessage that is on the 294bus after the specified timeout or %NULL if the bus is empty 295after the timeout expired. The message is taken from the bus. 296 297MT safe. 298</return> 299</function> 300 301 302<function name="gst_bus_timed_pop_filtered"> 303<description> 304Get a message from the bus whose type matches the message type mask @types, 305waiting up to the specified timeout (and discarding any messages that do not 306match the mask provided). 307 308If @timeout is 0, this function behaves like gst_bus_pop_filtered(). If 309@timeout is #GST_CLOCK_TIME_NONE, this function will block forever until a 310matching message was posted on the bus. 311 312 313</description> 314<parameters> 315<parameter name="bus"> 316<parameter_description> a #GstBus to pop from 317</parameter_description> 318</parameter> 319<parameter name="timeout"> 320<parameter_description> a timeout in nanoseconds, or GST_CLOCK_TIME_NONE to wait forever 321</parameter_description> 322</parameter> 323<parameter name="types"> 324<parameter_description> message types to take into account, GST_MESSAGE_ANY for any type 325</parameter_description> 326</parameter> 327</parameters> 328<return> a #GstMessage matching the 329filter in @types, or %NULL if no matching message was found on 330the bus until the timeout expired. The message is taken from 331the bus. 332 333MT safe. 334</return> 335</function> 336 337</root> 338