---
name: "DPMSQueryExtension"
section: "3x"
platform: "linux"
package: "libxext-dev"
version: "1:1.0.1-2"
release: "Debian 4.0 (Etch)"
platforms: ["linux"]
url: "https://new.carta.tech/DPMSQueryExtension/3x"
---

# DPMSQueryExtension(3x)

queries the X server to determine the availability of the DPMS Extension

## NAME

DPMSQueryExtension - queries the X server to determine the availability of the DPMS Extension

## SYNOPSIS

```
cc [ flag ... ] file ... -lXext [ library ... ]
#include <X11/extensions/dpms.h>
Bool DPMSQueryExtension
(
      Display *display,
      int *event_base,
      int *error_base
);
```

## ARGUMENTS

- *display*

  Specifies the connection to the X server

- *event\_base*

  Specifies the return location for the assigned base event

- *error\_base*

  Specifies the return location for the assigned base error

## DESCRIPTION

The  *DPMSQueryExtension* function queries the X server to determine the availability of the Display Power Management Signaling (DPMS)  Extension.  If the extension is available, it returns TRUE, and the *event\_base* and  *error\_base* are set to the base event and error numbers, respectively.  Otherwise, the  return value is FALSE, and the  values of *event\_base* and  *error\_base* are undefined.

## RETURN VALUES

- TRUE

  The  *DPMSQueryExtension* function returns TRUE if the extension is available,  and *event\_base* and  *error\_base* are set to the base event number and base error number for the extension,  respectively.

- FALSE

  The  *DPMSQueryExtension* function returns FALSE if extension is not available, and the values of *event\_base* and  *error\_base* are undefined.

## SEE ALSO

[**DPMSGetVersion**(3x)](/DPMSGetVersion/3x.md)