GstQuery

## GstQuery GstQuery — Dynamically register new query types. Provide functions to create queries, and to set and parse values in them. |

## Synopsis

    #include <gst/gst.h>

    struct              GstQuery;
    enum                GstQueryType;
    #define             GST_QUERY_TYPE_NAME                 (query)
    struct              GstQueryTypeDefinition;
    const gchar *       gst_query_type_get_name             (GstQueryType query);
    GQuark              gst_query_type_to_quark             (GstQueryType query);
    GstQueryType        gst_query_type_register             (const gchar *nick,
                                                             const gchar *description);
    GstQueryType        gst_query_type_get_by_nick          (const gchar *nick);
    gboolean            gst_query_types_contains            (const GstQueryType *types,
                                                             GstQueryType type);
    const GstQueryTypeDefinition * gst_query_type_get_details
                                                            (GstQueryType type);
    GstIterator *       gst_query_type_iterate_definitions  (void);
    GstQuery *          gst_query_ref                       (GstQuery *q);
    void                gst_query_unref                     (GstQuery *q);
    GstQuery *          gst_query_copy                      (const GstQuery *q);
    #define             gst_query_make_writable             (q)
    GstQuery *          gst_query_new_application           (GstQueryType type,
                                                             GstStructure *structure);
    GstStructure *      gst_query_get_structure             (GstQuery *query);
    GstQuery *          gst_query_new_convert               (GstFormat src_format,
                                                             gint64 value,
                                                             GstFormat dest_format);
    void                gst_query_set_convert               (GstQuery *query,
                                                             GstFormat src_format,
                                                             gint64 src_value,
                                                             GstFormat dest_format,
                                                             gint64 dest_value);
    void                gst_query_parse_convert             (GstQuery *query,
                                                             GstFormat *src_format,
                                                             gint64 *src_value,
                                                             GstFormat *dest_format,
                                                             gint64 *dest_value);
    GstQuery *          gst_query_new_position              (GstFormat format);
    void                gst_query_set_position              (GstQuery *query,
                                                             GstFormat format,
                                                             gint64 cur);
    void                gst_query_parse_position            (GstQuery *query,
                                                             GstFormat *format,
                                                             gint64 *cur);
    GstQuery *          gst_query_new_duration              (GstFormat format);
    void                gst_query_set_duration              (GstQuery *query,
                                                             GstFormat format,
                                                             gint64 duration);
    void                gst_query_parse_duration            (GstQuery *query,
                                                             GstFormat *format,
                                                             gint64 *duration);
    GstQuery *          gst_query_new_latency               (void);
    void                gst_query_parse_latency             (GstQuery *query,
                                                             gboolean *live,
                                                             GstClockTime *min_latency,
                                                             GstClockTime *max_latency);
    void                gst_query_set_latency               (GstQuery *query,
                                                             gboolean live,
                                                             GstClockTime min_latency,
                                                             GstClockTime max_latency);
    GstQuery *          gst_query_new_seeking               (GstFormat format);
    void                gst_query_set_seeking               (GstQuery *query,
                                                             GstFormat format,
                                                             gboolean seekable,
                                                             gint64 segment_start,
                                                             gint64 segment_end);
    void                gst_query_parse_seeking             (GstQuery *query,
                                                             GstFormat *format,
                                                             gboolean *seekable,
                                                             gint64 *segment_start,
                                                             gint64 *segment_end);
    GstQuery *          gst_query_new_formats               (void);
    void                gst_query_set_formats               (GstQuery *query,
                                                             gint n_formats,
                                                             ...);
    void                gst_query_set_formatsv              (GstQuery *query,
                                                             gint n_formats,
                                                             const GstFormat *formats);
    void                gst_query_parse_formats_length      (GstQuery *query,
                                                             guint *n_formats);
    void                gst_query_parse_formats_nth         (GstQuery *query,
                                                             guint nth,
                                                             GstFormat *format);
    GstQuery *          gst_query_new_segment               (GstFormat format);
    void                gst_query_set_segment               (GstQuery *query,
                                                             gdouble rate,
                                                             GstFormat format,
                                                             gint64 start_value,
                                                             gint64 stop_value);
    void                gst_query_parse_segment             (GstQuery *query,
                                                             gdouble *rate,
                                                             GstFormat *format,
                                                             gint64 *start_value,
                                                             gint64 *stop_value);
    enum                GstBufferingMode;
    GstQuery *          gst_query_new_buffering             (GstFormat format);
    void                gst_query_set_buffering_percent     (GstQuery *query,
                                                             gboolean busy,
                                                             gint percent);
    void                gst_query_parse_buffering_percent   (GstQuery *query,
                                                             gboolean *busy,
                                                             gint *percent);
    void                gst_query_set_buffering_stats       (GstQuery *query,
                                                             GstBufferingMode mode,
                                                             gint avg_in,
                                                             gint avg_out,
                                                             gint64 buffering_left);
    void                gst_query_parse_buffering_stats     (GstQuery *query,
                                                             GstBufferingMode *mode,
                                                             gint *avg_in,
                                                             gint *avg_out,
                                                             gint64 *buffering_left);
    void                gst_query_set_buffering_range       (GstQuery *query,
                                                             GstFormat format,
                                                             gint64 start,
                                                             gint64 stop,
                                                             gint64 estimated_total);
    void                gst_query_parse_buffering_range     (GstQuery *query,
                                                             GstFormat *format,
                                                             gint64 *start,
                                                             gint64 *stop,
                                                             gint64 *estimated_total);
    gboolean            gst_query_add_buffering_range       (GstQuery *query,
                                                             gint64 start,
                                                             gint64 stop);
    guint               gst_query_get_n_buffering_ranges    (GstQuery *query);
    gboolean            gst_query_parse_nth_buffering_range (GstQuery *query,
                                                             guint index,
                                                             gint64 *start,
                                                             gint64 *stop);
    GstQuery *          gst_query_new_uri                   (void);
    void                gst_query_parse_uri                 (GstQuery *query,
                                                             gchar **uri);
    void                gst_query_set_uri                   (GstQuery *query,
                                                             const gchar *uri);

## Description

GstQuery functions are used to register new query types to the gstreamer core and use them. Queries can be performed on pads (`gst_pad_query()`) and elements (`gst_element_query()`). Please note that some queries might need a running pipeline to work.

Queries can be created using the gst_query_new_*() functions. Query values can be set using gst_query_set_*(), and parsed using gst_query_parse_*() helpers.

The following example shows how to query the duration of a pipeline:

Example 16. Query duration on a pipeline

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    GstQuery *query;
    gboolean res;
    query = gst_query_new_duration (GST_FORMAT_TIME);
    res = gst_element_query (pipeline, query);
    if (res) {
      gint64 duration;
      gst_query_parse_duration (query, NULL, &duration);
      g_print ("duration = %"GST_TIME_FORMAT, GST_TIME_ARGS (duration));
    }
    else {
      g_print ("duration query failed...");
    }
    gst_query_unref (query);

Last reviewed on 2006-02-14 (0.10.4)

## Details

### struct GstQuery

    struct GstQuery {
      GstMiniObject mini_object;

      GstQueryType type;

      GstStructure *structure;
    };

The GstQuery structure.

GstMiniObject `mini_object`; | The parent GstMiniObject type
GstQueryType `type`; | the GstQueryType
GstStructure *`structure`; | the GstStructure containing the query details.

### enum GstQueryType

    typedef enum {
      GST_QUERY_NONE = 0,
      GST_QUERY_POSITION,
      GST_QUERY_DURATION,
      GST_QUERY_LATENCY,
      GST_QUERY_JITTER,     /* not in draft-query, necessary? */
      GST_QUERY_RATE,
      GST_QUERY_SEEKING,
      GST_QUERY_SEGMENT,
      GST_QUERY_CONVERT,
      GST_QUERY_FORMATS,
      GST_QUERY_BUFFERING,
      GST_QUERY_CUSTOM,
      GST_QUERY_URI
    } GstQueryType;

Standard predefined Query types

`GST_QUERY_NONE` | invalid query type
`GST_QUERY_POSITION` | current position in stream
`GST_QUERY_DURATION` | total duration of the stream
`GST_QUERY_LATENCY` | latency of stream
`GST_QUERY_JITTER` | current jitter of stream
`GST_QUERY_RATE` | current rate of the stream
`GST_QUERY_SEEKING` | seeking capabilities
`GST_QUERY_SEGMENT` | segment start/stop positions
`GST_QUERY_CONVERT` | convert values between formats
`GST_QUERY_FORMATS` | query supported formats for convert
`GST_QUERY_BUFFERING` | query available media for efficient seeking. Since 0.10.20.
`GST_QUERY_CUSTOM` | a custom application or element defined query. Since 0.10.22.
`GST_QUERY_URI` | query the URI of the source or sink. Since 0.10.22.

### GST_QUERY_TYPE_NAME()

    #define GST_QUERY_TYPE_NAME(query) (gst_query_type_get_name(GST_QUERY_TYPE(query)))

Get a constant string representation of the GstQueryType of the query.

`query` : | the query to query

Since 0.10.4

### struct GstQueryTypeDefinition

    struct GstQueryTypeDefinition {
      GstQueryType   value;
      const gchar   *nick;
      const gchar   *description;
      GQuark         quark;
    };

A Query Type definition

GstQueryType `value`; | the unique id of the Query type
const gchar *`nick`; | a short nick
const gchar *`description`; | a longer description of the query type
GQuark `quark`; | the quark for the nick

### gst_query_type_get_name ()

    const gchar *       gst_query_type_get_name             (GstQueryType query);

Get a printable name for the given query type. Do not modify or free.

`query` : | the query type
Returns : | a reference to the static name of the query.

### gst_query_type_to_quark ()

    GQuark              gst_query_type_to_quark             (GstQueryType query);

Get the unique quark for the given query type.

`query` : | the query type
Returns : | the quark associated with the query type

### gst_query_type_register ()

    GstQueryType        gst_query_type_register             (const gchar *nick,
                                                             const gchar *description);

Create a new GstQueryType based on the nick or return an already registered query with that nick

`nick` : | The nick of the new query
`description` : | The description of the new query
Returns : | A new GstQueryType or an already registered query with the same nick.

### gst_query_type_get_by_nick ()

    GstQueryType        gst_query_type_get_by_nick          (const gchar *nick);

Get the query type registered with `nick`.

`nick` : | The nick of the query
Returns : | The query registered with `nick` or GST_QUERY_NONE if the query was not registered.

### gst_query_types_contains ()

    gboolean            gst_query_types_contains            (const GstQueryType *types,
                                                             GstQueryType type);

See if the given GstQueryType is inside the `types` query types array.

`types` : | The query array to search
`type` : | the GstQueryType to find
Returns : | TRUE if the type is found inside the array

### gst_query_type_get_details ()

    const GstQueryTypeDefinition * gst_query_type_get_details
                                                            (GstQueryType type);

Get details about the given GstQueryType.

`type` : | a GstQueryType
Returns : | The GstQueryTypeDefinition for `type` or NULL on failure.

### gst_query_type_iterate_definitions ()

    GstIterator *       gst_query_type_iterate_definitions  (void);

Get a GstIterator of all the registered query types. The definitions iterated over are read only.

Free-function: gst_iterator_free

Returns : | a GstIterator of GstQueryTypeDefinition. [transfer full]

### gst_query_ref ()

    GstQuery *          gst_query_ref                       (GstQuery *q);

Increases the refcount of the given query by one.

`q` : | a GstQuery to increase the refcount of.
Returns : | `q`

### gst_query_unref ()

    void                gst_query_unref                     (GstQuery *q);

Decreases the refcount of the query. If the refcount reaches 0, the query will be freed.

`q` : | a GstQuery to decrease the refcount of.

### gst_query_copy ()

    GstQuery *          gst_query_copy                      (const GstQuery *q);

Copies the given query using the copy function of the parent GstStructure.

Free-function: gst_query_unref

`q` : | a GstQuery to copy.
Returns : | a new copy of `q`. [transfer full]

### gst_query_make_writable()

    #define         gst_query_make_writable(q)      GST_QUERY_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (q)))

Makes a writable query from the given query.

`q` : | a GstQuery to make writable. [transfer full]
Returns : | a new writable query (possibly same as `q`). [transfer full]

### gst_query_new_application ()

    GstQuery *          gst_query_new_application           (GstQueryType type,
                                                             GstStructure *structure);

Constructs a new custom application query object. Use `gst_query_unref()` when done with it.

Free-function: gst_query_unref

`type` : | the query type
`structure` : | a structure for the query
Returns : | a new GstQuery. [transfer full]

### gst_query_get_structure ()

    GstStructure *      gst_query_get_structure             (GstQuery *query);

Get the structure of a query.

`query` : | a GstQuery
Returns : | the GstStructure of the query. The structure is still owned by the query and will therefore be freed when the query is unreffed. [transfer none]

### gst_query_new_convert ()

    GstQuery *          gst_query_new_convert               (GstFormat src_format,
                                                             gint64 value,
                                                             GstFormat dest_format);

Constructs a new convert query object. Use `gst_query_unref()` when done with it. A convert query is used to ask for a conversion between one format and another.

Free-function: gst_query_unref

`src_format` : | the source GstFormat for the new query
`value` : | the value to convert
`dest_format` : | the target GstFormat
Returns : | a GstQuery. [transfer full]

### gst_query_set_convert ()

    void                gst_query_set_convert               (GstQuery *query,
                                                             GstFormat src_format,
                                                             gint64 src_value,
                                                             GstFormat dest_format,
                                                             gint64 dest_value);

Answer a convert query by setting the requested values.

`query` : | a GstQuery
`src_format` : | the source GstFormat
`src_value` : | the source value
`dest_format` : | the destination GstFormat
`dest_value` : | the destination value

### gst_query_parse_convert ()

    void                gst_query_parse_convert             (GstQuery *query,
                                                             GstFormat *src_format,
                                                             gint64 *src_value,
                                                             GstFormat *dest_format,
                                                             gint64 *dest_value);

Parse a convert query answer. Any of `src_format`, `src_value`, `dest_format`, and `dest_value` may be NULL, in which case that value is omitted.

`query` : | a GstQuery
`src_format` : | the storage for the GstFormat of the source value, or NULL. [out][allow-none]
`src_value` : | the storage for the source value, or NULL. [out][allow-none]
`dest_format` : | the storage for the GstFormat of the destination value, or NULL. [out][allow-none]
`dest_value` : | the storage for the destination value, or NULL. [out][allow-none]

### gst_query_new_position ()

    GstQuery *          gst_query_new_position              (GstFormat format);

Constructs a new query stream position query object. Use `gst_query_unref()` when done with it. A position query is used to query the current position of playback in the streams, in some format.

Free-function: gst_query_unref

`format` : | the default GstFormat for the new query
Returns : | a new GstQuery. [transfer full]

### gst_query_set_position ()

    void                gst_query_set_position              (GstQuery *query,
                                                             GstFormat format,
                                                             gint64 cur);

Answer a position query by setting the requested value in the given format.

`query` : | a GstQuery with query type GST_QUERY_POSITION
`format` : | the requested GstFormat
`cur` : | the position to set

### gst_query_parse_position ()

    void                gst_query_parse_position            (GstQuery *query,
                                                             GstFormat *format,
                                                             gint64 *cur);

Parse a position query, writing the format into `format`, and the position into `cur`, if the respective parameters are non-NULL.

`query` : | a GstQuery
`format` : | the storage for the GstFormat of the position values (may be NULL). [out][allow-none]
`cur` : | the storage for the current position (may be NULL). [out][allow-none]

### gst_query_new_duration ()

    GstQuery *          gst_query_new_duration              (GstFormat format);

Constructs a new stream duration query object to query in the given format. Use `gst_query_unref()` when done with it. A duration query will give the total length of the stream.

Free-function: gst_query_unref

`format` : | the GstFormat for this duration query
Returns : | a new GstQuery. [transfer full]

### gst_query_set_duration ()

    void                gst_query_set_duration              (GstQuery *query,
                                                             GstFormat format,
                                                             gint64 duration);

Answer a duration query by setting the requested value in the given format.

`query` : | a GstQuery
`format` : | the GstFormat for the duration
`duration` : | the duration of the stream

### gst_query_parse_duration ()

    void                gst_query_parse_duration            (GstQuery *query,
                                                             GstFormat *format,
                                                             gint64 *duration);

Parse a duration query answer. Write the format of the duration into `format`, and the value into `duration`, if the respective variables are non-NULL.

`query` : | a GstQuery
`format` : | the storage for the GstFormat of the duration value, or NULL. [out][allow-none]
`duration` : | the storage for the total duration, or NULL. [out][allow-none]

### gst_query_new_latency ()

    GstQuery *          gst_query_new_latency               (void);

Constructs a new latency query object. Use `gst_query_unref()` when done with it. A latency query is usually performed by sinks to compensate for additional latency introduced by elements in the pipeline.

Free-function: gst_query_unref

Returns : | a GstQuery. [transfer full]

Since 0.10.12

### gst_query_parse_latency ()

    void                gst_query_parse_latency             (GstQuery *query,
                                                             gboolean *live,
                                                             GstClockTime *min_latency,
                                                             GstClockTime *max_latency);

Parse a latency query answer.

`query` : | a GstQuery
`live` : | storage for live or NULL. [out][allow-none]
`min_latency` : | the storage for the min latency or NULL. [out][allow-none]
`max_latency` : | the storage for the max latency or NULL. [out][allow-none]

Since 0.10.12

### gst_query_set_latency ()

    void                gst_query_set_latency               (GstQuery *query,
                                                             gboolean live,
                                                             GstClockTime min_latency,
                                                             GstClockTime max_latency);

Answer a latency query by setting the requested values in the given format.

`query` : | a GstQuery
`live` : | if there is a live element upstream
`min_latency` : | the minimal latency of the live element
`max_latency` : | the maximal latency of the live element

Since 0.10.12

### gst_query_new_seeking ()

    GstQuery *          gst_query_new_seeking               (GstFormat format);

Constructs a new query object for querying seeking properties of the stream.

Free-function: gst_query_unref

`format` : | the default GstFormat for the new query
Returns : | a new GstQuery. [transfer full]

### gst_query_set_seeking ()

    void                gst_query_set_seeking               (GstQuery *query,
                                                             GstFormat format,
                                                             gboolean seekable,
                                                             gint64 segment_start,
                                                             gint64 segment_end);

Set the seeking query result fields in `query`.

`query` : | a GstQuery
`format` : | the format to set for the `segment_start` and `segment_end` values
`seekable` : | the seekable flag to set
`segment_start` : | the segment_start to set
`segment_end` : | the segment_end to set

### gst_query_parse_seeking ()

    void                gst_query_parse_seeking             (GstQuery *query,
                                                             GstFormat *format,
                                                             gboolean *seekable,
                                                             gint64 *segment_start,
                                                             gint64 *segment_end);

Parse a seeking query, writing the format into `format`, and other results into the passed parameters, if the respective parameters are non-NULL

`query` : | a GST_QUERY_SEEKING type query GstQuery
`format` : | the format to set for the `segment_start` and `segment_end` values, or NULL. [out][allow-none]
`seekable` : | the seekable flag to set, or NULL. [out][allow-none]
`segment_start` : | the segment_start to set, or NULL. [out][allow-none]
`segment_end` : | the segment_end to set, or NULL. [out][allow-none]

### gst_query_new_formats ()

    GstQuery *          gst_query_new_formats               (void);

Constructs a new query object for querying formats of the stream.

Free-function: gst_query_unref

Returns : | a new GstQuery. [transfer full]

Since 0.10.4

### gst_query_set_formats ()

    void                gst_query_set_formats               (GstQuery *query,
                                                             gint n_formats,
                                                             ...);

Set the formats query result fields in `query`. The number of formats passed must be equal to `n_formats`.

`query` : | a GstQuery
`n_formats` : | the number of formats to set.
`...` : | A number of `GstFormats` equal to `n_formats`.

### gst_query_set_formatsv ()

    void                gst_query_set_formatsv              (GstQuery *query,
                                                             gint n_formats,
                                                             const GstFormat *formats);

Set the formats query result fields in `query`. The number of formats passed in the `formats` array must be equal to `n_formats`.

`query` : | a GstQuery
`n_formats` : | the number of formats to set.
`formats` : | an array containing `n_formats` `GstFormat` values. [in][array length=n_formats]

Since 0.10.4

### gst_query_parse_formats_length ()

    void                gst_query_parse_formats_length      (GstQuery *query,
                                                             guint *n_formats);

Parse the number of formats in the formats `query`.

`query` : | a GstQuery
`n_formats` : | the number of formats in this query. [out]

Since 0.10.4

### gst_query_parse_formats_nth ()

    void                gst_query_parse_formats_nth         (GstQuery *query,
                                                             guint nth,
                                                             GstFormat *format);

Parse the format query and retrieve the `nth` format from it into `format`. If the list contains less elements than `nth`, `format` will be set to GST_FORMAT_UNDEFINED.

`query` : | a GstQuery
`nth` : | the nth format to retrieve. [out]
`format` : | a pointer to store the nth format. [out]

Since 0.10.4

### gst_query_new_segment ()

    GstQuery *          gst_query_new_segment               (GstFormat format);

Constructs a new segment query object. Use `gst_query_unref()` when done with it. A segment query is used to discover information about the currently configured segment for playback.

Free-function: gst_query_unref

`format` : | the GstFormat for the new query
Returns : | a new GstQuery. [transfer full]

### gst_query_set_segment ()

    void                gst_query_set_segment               (GstQuery *query,
                                                             gdouble rate,
                                                             GstFormat format,
                                                             gint64 start_value,
                                                             gint64 stop_value);

Answer a segment query by setting the requested values. The normal playback segment of a pipeline is 0 to duration at the default rate of 1.0. If a seek was performed on the pipeline to play a different segment, this query will return the range specified in the last seek.

`start_value` and `stop_value` will respectively contain the configured playback range start and stop values expressed in `format`. The values are always between 0 and the duration of the media and `start_value` <= `stop_value`. `rate` will contain the playback rate. For negative rates, playback will actually happen from `stop_value` to `start_value`.

`query` : | a GstQuery
`rate` : | the rate of the segment
`format` : | the GstFormat of the segment values (`start_value` and `stop_value`)
`start_value` : | the start value
`stop_value` : | the stop value

### gst_query_parse_segment ()

    void                gst_query_parse_segment             (GstQuery *query,
                                                             gdouble *rate,
                                                             GstFormat *format,
                                                             gint64 *start_value,
                                                             gint64 *stop_value);

Parse a segment query answer. Any of `rate`, `format`, `start_value`, and `stop_value` may be NULL, which will cause this value to be omitted.

See `gst_query_set_segment()` for an explanation of the function arguments.

`query` : | a GstQuery
`rate` : | the storage for the rate of the segment, or NULL. [out][allow-none]
`format` : | the storage for the GstFormat of the values, or NULL. [out][allow-none]
`start_value` : | the storage for the start value, or NULL. [out][allow-none]
`stop_value` : | the storage for the stop value, or NULL. [out][allow-none]

### enum GstBufferingMode

    typedef enum {
      GST_BUFFERING_STREAM,
      GST_BUFFERING_DOWNLOAD,
      GST_BUFFERING_TIMESHIFT,
      GST_BUFFERING_LIVE
    } GstBufferingMode;

The different types of buffering methods.

`GST_BUFFERING_STREAM` | a small amount of data is buffered
`GST_BUFFERING_DOWNLOAD` | the stream is being downloaded
`GST_BUFFERING_TIMESHIFT` | the stream is being downloaded in a ringbuffer
`GST_BUFFERING_LIVE` | the stream is a live stream

### gst_query_new_buffering ()

    GstQuery *          gst_query_new_buffering             (GstFormat format);

Constructs a new query object for querying the buffering status of a stream.

Free-function: gst_query_new

`format` : | the default GstFormat for the new query
Returns : | a new GstQuery. [transfer full]

Since 0.10.20

### gst_query_set_buffering_percent ()

    void                gst_query_set_buffering_percent     (GstQuery *query,
                                                             gboolean busy,
                                                             gint percent);

Set the percentage of buffered data. This is a value between 0 and 100. The `busy` indicator is `TRUE` when the buffering is in progress.

`query` : | A valid GstQuery of type GST_QUERY_BUFFERING.
`busy` : | if buffering is busy
`percent` : | a buffering percent

Since 0.10.20

### gst_query_parse_buffering_percent ()

    void                gst_query_parse_buffering_percent   (GstQuery *query,
                                                             gboolean *busy,
                                                             gint *percent);

Get the percentage of buffered data. This is a value between 0 and 100. The `busy` indicator is `TRUE` when the buffering is in progress.

`query` : | A valid GstQuery of type GST_QUERY_BUFFERING.
`busy` : | if buffering is busy, or NULL. [out][allow-none]
`percent` : | a buffering percent, or NULL. [out][allow-none]

Since 0.10.20

### gst_query_set_buffering_stats ()

    void                gst_query_set_buffering_stats       (GstQuery *query,
                                                             GstBufferingMode mode,
                                                             gint avg_in,
                                                             gint avg_out,
                                                             gint64 buffering_left);

Configures the buffering stats values in `query`.

`query` : | A valid GstQuery of type GST_QUERY_BUFFERING.
`mode` : | a buffering mode
`avg_in` : | the average input rate
`avg_out` : | the average output rate
`buffering_left` : | amount of buffering time left

Since 0.10.20

### gst_query_parse_buffering_stats ()

    void                gst_query_parse_buffering_stats     (GstQuery *query,
                                                             GstBufferingMode *mode,
                                                             gint *avg_in,
                                                             gint *avg_out,
                                                             gint64 *buffering_left);

Extracts the buffering stats values from `query`.

`query` : | A valid GstQuery of type GST_QUERY_BUFFERING.
`mode` : | a buffering mode, or NULL. [out][allow-none]
`avg_in` : | the average input rate, or NULL. [out][allow-none]
`avg_out` : | the average output rat, or NULLe. [out][allow-none]
`buffering_left` : | amount of buffering time left, or NULL. [out][allow-none]

Since 0.10.20

### gst_query_set_buffering_range ()

    void                gst_query_set_buffering_range       (GstQuery *query,
                                                             GstFormat format,
                                                             gint64 start,
                                                             gint64 stop,
                                                             gint64 estimated_total);

Set the available query result fields in `query`.

`query` : | a GstQuery
`format` : | the format to set for the `start` and `stop` values
`start` : | the start to set
`stop` : | the stop to set
`estimated_total` : | estimated total amount of download time

Since 0.10.20

### gst_query_parse_buffering_range ()

    void                gst_query_parse_buffering_range     (GstQuery *query,
                                                             GstFormat *format,
                                                             gint64 *start,
                                                             gint64 *stop,
                                                             gint64 *estimated_total);

Parse an available query, writing the format into `format`, and other results into the passed parameters, if the respective parameters are non-NULL

`query` : | a GST_QUERY_BUFFERING type query GstQuery
`format` : | the format to set for the `segment_start` and `segment_end` values, or NULL. [out][allow-none]
`start` : | the start to set, or NULL. [out][allow-none]
`stop` : | the stop to set, or NULL. [out][allow-none]
`estimated_total` : | estimated total amount of download time, or NULL. [out][allow-none]

Since 0.10.20

### gst_query_add_buffering_range ()

    gboolean            gst_query_add_buffering_range       (GstQuery *query,
                                                             gint64 start,
                                                             gint64 stop);

Set the buffering-ranges array field in `query`. The current last start position of the array should be inferior to `start`.

`query` : | a GST_QUERY_BUFFERING type query GstQuery
`start` : | start position of the range
`stop` : | stop position of the range
Returns : | a gboolean indicating if the range was added or not.

Since 0.10.31

### gst_query_get_n_buffering_ranges ()

    guint               gst_query_get_n_buffering_ranges    (GstQuery *query);

Retrieve the number of values currently stored in the buffered-ranges array of the query's structure.

`query` : | a GST_QUERY_BUFFERING type query GstQuery
Returns : | the range array size as a guint.

Since 0.10.31

### gst_query_parse_nth_buffering_range ()

    gboolean            gst_query_parse_nth_buffering_range (GstQuery *query,
                                                             guint index,
                                                             gint64 *start,
                                                             gint64 *stop);

Parse an available query and get the start and stop values stored at the `index` of the buffered ranges array.

`query` : | a GST_QUERY_BUFFERING type query GstQuery
`index` : | position in the buffered-ranges array to read
`start` : | the start position to set, or NULL. [out][allow-none]
`stop` : | the stop position to set, or NULL. [out][allow-none]
Returns : | a gboolean indicating if the parsing succeeded.

Since 0.10.31

### gst_query_new_uri ()

    GstQuery *          gst_query_new_uri                   (void);

Constructs a new query URI query object. Use `gst_query_unref()` when done with it. An URI query is used to query the current URI that is used by the source or sink.

Free-function: gst_query_unref

Returns : | a new GstQuery. [transfer full]

Since 0.10.22

### gst_query_parse_uri ()

    void                gst_query_parse_uri                 (GstQuery *query,
                                                             gchar **uri);

Parse an URI query, writing the URI into `uri` as a newly allocated string, if the respective parameters are non-NULL. Free the string with `g_free()` after usage.

`query` : | a GstQuery
`uri` : | the storage for the current URI (may be NULL). [out callee-allocates][allow-none]

Since 0.10.22

### gst_query_set_uri ()

    void                gst_query_set_uri                   (GstQuery *query,
                                                             const gchar *uri);

Answer a URI query by setting the requested URI.

`query` : | a GstQuery with query type GST_QUERY_URI
`uri` : | the URI to set

Since 0.10.22

## See Also

GstPad, GstElement