Xen devel - Apr 2013 - Where is the location of the log file generated by .c files

Hi,

I want to add some logs in xc_domain_save.c file to monitor the whole process
when migration.  And I used the "DBGPRINTF(..)" method, which has
already been defined in .c file. But I don''t know where this method
outputs the log messages. I have found that the "var/log/xen/xend.log"
file records the log information for Phython files. But does anyone know the
location of the log file generated by .c files?
  
Thank you!