libxrdeveloper's documentation
#define xr_trace (   mask,
  fmt,
  args... 
)    do { if (G_UNLIKELY(xr_debug_enabled & mask)) _xr_debug(G_STRFUNC, fmt, ## args); } while(0)

Conditional trace message.

Parameters:
mask XR_DEBUG_* constant that enables this message.
fmt Message format (printf like).
args Variable arguments.
Documentation for libxr, Sun Nov 28 2010 15:38:20.