XdbeQueryExtension - returns the version of DBE supported by the server.
#include <X11/extensions/Xdbe.h>
Status XdbeQueryExtension(
Display *dpy,
int *major_version_return,
int *minor_version_return)
Sets major_version_return and minor_version_return to the major
and minor DBE protocol version supported by the server. If the DBE library is
compatible with the version returned by the server, this function returns
non-zero. If dpy does not support the DBE extension, or if there was an
error during communication with the server, or if the server and library
protocol versions are incompatible, this function returns zero. No other Xdbe
functions may be called before this function. If a client violates this rule,
the effects of all subsequent Xdbe calls that it makes are undefined.
DBE, XdbeAllocateBackBufferName(), XdbeBeginIdiom(),
XdbeDeallocateBackBufferName(), XdbeEndIdiom(),
XdbeFreeVisualInfo(), XdbeGetBackBufferAttributes(),
XdbeGetVisualInfo(), XdbeSwapBuffers().