XvQueryAdaptors(3X) UNIX Programmer's Manual XvQueryAdaptors(3X)
Name
XvQueryAdaptors - return adaptor information for a screen
Syntax
#include <X11/extensions/Xvlib.h>
XvQueryAdaptors(dpy, win, p_num_adaptors, pp_adaptor_info)
Display *dpy;
Drawable draw;
int *p_num_adaptors;
XvAdaptorInfo **pp_adaptor_info;
Arguments
dpy Specifies the display screen on which the Xv Server
is to accept requests from Xv clients. If the
display option is not specified, Xv uses the display
screen specified by your DISPLAY environment vari-
able. The display option has the format
hostname:number. Using two colons (::) instead of
one (:) indicates that DECnet is to be used for
transport.
draw Specifies a drawable of the screen for which the
adaptor information is desired.
p_num_adaptors
A pointer to where the number of adaptors for the
specified screen is returned.
pp_adaptor_info
A pointer to where the list of returned adaptor
information is returned.
Description
XvQueryAdaptors(3X) returns an video adaptor information for
the screen of the specified drawable. The XvAdaptorInfo
structure has the following organization:
typedef struct {
XvPortID base_id;
unsigned long num_ports;
char type;
char *name;
unsigned long num_formats;
XvFormat *formats;
unsigned long num_adaptors;
} XvAdaptorInfo;
base_id The resource ID of the first adaptor port.
XFree86 Version 4.5.0 1
XvQueryAdaptors(3X) UNIX Programmer's Manual XvQueryAdaptors(3X)
num_ports
The number of ports supported by the adaptor.
type A bit mask with the value XvInputMask asserted if
the adaptor supports video input, and value XvOut-
putMask asserted if the adaptor supports video out-
put.
name A vendor specific name that identifies the adaptor.
num_formats
The number of depth/visual id formats supported by
the adaptor.
formats A pointer to an array of XvFormat structures.
The XvFormat structure has the following organization:
typedef struct {
char depth;
unsigned long visual_id;
} XvFormat;
depth A drawable depth supported by the adaptor.
visual_id
A visual-id supported for the given depth by the
adaptor.
Returned Values
[Success]
Returned if XvQueryAdaptors(3X) completed success-
fully.
[XvBadExtension]
Returned if the Xv extension is unavailable.
[XvBadAlloc]
Returned if XvQueryAdaptors(3X) failed to allocate
memory to process the request.
Diagnostics
[Drawable]
Returned if the requested drawable does not exist.
See Also
XvFreeAdaptorInfo(3X)
XFree86 Version 4.5.0 2