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XvQueryPortAttributes

NAME

XvQueryPortAttributes - return list of attributes of a video port

SYNOPSIS

#include <X11/extensions/Xvlib.h>

 XvAttribute* XvQueryPortAttributes(Display *dpy,
                  XvPortID port,  int *p_num_attributes);
 

ARGUMENTS

dpy

Specifies the connection to the X server.

port

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

p_num_attributes

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

DESCRIPTION

XvQueryPortAttributes(3)returnsthenumberofattributes and an array of XvAttributes valid for the given port. The array may be freed with XFree(3).

RETURN VALUES

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.

min_value

The minimum attribute values which are valid for the driver.

The maximum attribute values which are valid for the driver.

name

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

DIAGNOSTICS

[XvBadPort]

Generated if the requested port does not exist.

SEE ALSO

XvGetPortAttribute(3), XvSetPortAttribute(3)