Nvidia Quadro FX 4500 Software Manual page 82

C 5
HAPTER
API Control
);
This function is the same as XNVCTRLSetAttribute(), and returns True if the operation
succeeds, otherwise False.
XNVCTRLQueryAttribute()
Bool XNVCTRLQueryAttribute (
);
This function returns True if the attribute exists, otherwise False.
If XNVCTRLQueryAttribute returns True, value will contain the value of the specified
attribute. Not all attributes require the display_mask parameter. See
Attributes" on page 67
Possible errors:
• BadValue - The screen doesnʹt exist.
• BadMatch - The NVIDIA driver is not present on that screen.
XNVCTRLQueryStringAttribute()
Bool XNVCTRLQueryStringAttribute (
);
This function returns True if the attribute exists, otherwise False.
If XNVCTRLQueryStringAttribute returns True, *ptr will point to an allocated string
containing the string attribute requested. It is the callerʹs responsibility to free the string
when done.
Possible errors:
78
Display *dpy,
int screen,
unsigned int display_mask,
unsigned int attribute,
int *value
for details.
Display *dpy,
int screen,
unsigned int display_mask,
unsigned int attribute,
char **ptr
Quadro FX 4500/5500 SDI User's Guide– Version 2.0
"NV_CTRL_GVO
NVIDIA Corporation