 [det]openlog(+Ident:atom, 
+Options:list(atom), +Facility:atom)
[det]openlog(+Ident:atom, 
+Options:list(atom), +Facility:atom)openlog() 
library call. If the library call is successful, it runs at_halt(closelog) 
to ensure closing the system log on clean exit.
| Ident | prepended to every message, and is typically set to the program name. | 
| Options | is a list of options. Values are 
corresponding C options, after removing =LOG_= and translation to lower 
case: cons,ndelay,nowait,odelay,perror,pid. | 
| Facility | is one of auth,authpriv,cron,daemon,ftp,kern,local0...local7,lpr,mail,news,syslog,useroruucp. |