XvGetPortAttribute (3)
NAME
XvGetPortAttribute - return current port attribute valueSYNOPSIS
#include <X11/extensions/Xvlib.h>
int XvGetPortAttribute(Display *dpy, XvPortID port,
Atom attribute, int p_value);
ARGUMENTS
- 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.
DESCRIPTION
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 |
RETURN VALUES
- [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.
DIAGNOSTICS
- [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.