ref: b3dc2af6d671b6311ccfc8a5f053dc85151cb7ed
dir: /sys/src/cmd/upas/imap4d/debug.c/
#include "imap4d.h" char logfile[28] = "imap4"; void debuglog(char *fmt, ...) { char buf[1024]; va_list arg; if(debug == 0) return; va_start(arg, fmt); vseprint(buf, buf + sizeof buf, fmt, arg); va_end(arg); syslog(0, logfile, "[%s:%d] %s", username, getpid(), buf); } void ilog(char *fmt, ...) { char buf[1024]; va_list arg; va_start(arg, fmt); vseprint(buf, buf + sizeof buf, fmt, arg); va_end(arg); syslog(0, logfile, "[%s:%d] %s", username, getpid(), buf); }