XvGetPortAttribute - return current port attribute value
#include <X11/extensions/Xvlib.h>
int XvGetPortAttribute(Display *dpy, XvPortID port,
Atom attribute, int p_value);
- dpy
- Specifies the connection to the X server.
- port
- Specifies the port, associated with the given display, for which the
attribute values are to be returned.
- attribute
- An atom that identifies the attribute to be queried by this request.
Control atoms are obtained using the XInternAtom request with a string
from the following table.
- p_value
- Pointer to the location where the attribute value is written on
return.
XvGetPortAttribute(3) returns the current value of the requested port
attribute in the integer pointed to by p_value. The attribute is
identified using an Atom that equates to the attribute name. The XInternAtom
request can be used with one of the strings below to return a matching Atom.
Attribute String |
Type |
Default |
"XV_ENCODING" |
XvEncodingID |
Server dependent |
"XV_HUE" |
[-1000...1000] |
0 |
"XV_SATURATION" |
[-1000...1000] |
0 |
"XV_BRIGHTNESS" |
[-1000...1000] |
0 |
"XV_CONTRAST" |
[-1000...1000] |
0 |
- [Success]
- Returned if XvGetPortAttribute(3) completed successfully.
- [XvBadExtension]
- Returned if the Xv extension is unavailable.
- [XvBadAlloc]
- Returned if XvGetPortAttribute(3) failed to allocate memory to
process the request.
- [XvBadPort]
- Generated if the requested port does not exist.
- [BadMatch]
- Generated if the requested attribute atom does not specify an attribute
supported by the adaptor.
XvSetPortAttribute(3), XvPortNotify(3)