XvQueryPortAttributes (3) Linux Manual Page

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.