XvQueryPortAttributes (3)
NAME
XvQueryPortAttributes - return list of attributes of a video portSYNOPSIS
#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.