XvQueryPortAttributes − return list of attributes of a video


,XvAttribute* XvQueryPortAttributes(Display *dpy
,  int *                 XvPortID port

dpy     Specifies the connection to the X server.

port    Specifies the port whose adaptor is to be queried
        for its list of attributes.

        A pointer to where the number of attributes returned
        in the array is written.

and an array of XvAttributes valid for the given port.  The
array may be freed with

XvAttribute has the following structure:

    typedef struct {
      int flags;
      int min_value;
      int max_value;
      char *name;
    } XvAttribute;

flags   May be XvGettable or XvSettable or both OR’d
        together indicating the particular attribute is
        readable, writeable or readable and writeable.

        The minimum attribute values which are valid for the

        The maximum attribute values which are valid for the

name    A string describing the name of the attribute that
        may be used to retrieve the Atom for the particular

        Generated if the requested port does not exist.