Name
XvGetPortAttribute - return current port attribute value
Syntax
#include
XvGetPortAttribute(_d_p_y_, _p_o_r_t_, _a_t_t_r_i_b_u_t_e_, _p___v_a_l_u_e)
DDiissppllaayy _*_d_p_y;
XXvvPPoorrttIIDD _p_o_r_t;
AAttoomm _a_t_t_r_i_b_u_t_e;
iinntt _*_p___v_a_l_u_e;
Arguments
-
_d_p_y
Specifies the display screen on which the
-
X Server is to accept requests from X clients. If the
display option is not specified, X uses the display screen
specified by your DISPLAY environment variable. The display
option has the format hostname:number. Using two colons
(::) instead of one (:) indicates that DECnet is to be used
for transport.
-
_p_o_r_t
Specifies the port, associated with the given display, for
-
which the attribute values are to be returned.
-
_a_t_t_r_i_b_u_t_e
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___v_a_l_u_e
Pointer to the location where the attribute value is written on
-
return.
Description
XvGetPortAttribute(3X) returns the current value of the requested
port attribute in the integer pointed to by _p___v_a_l_u_e.
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
Returned Values
-
[Success]
Returned if XvGetPortAttribute(3X) completed successfully.
-
-
[XvBadExtension]
Returned if the Xv extension is unavailable.
-
-
[XvBadAlloc]
Returned if XvGetPortAttribute(3X) 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.
See Also
XvSetPortAttribute(3X), XvPortNotify(3X)