Write a message to the system log
#include <syslog.h> void syslog( int priority, const char * message, ...)
The formatting characters that you use in the message determine any additional arguments.
Use the -l c option to qcc to link against this library. This library is usually included automatically.
The syslog() function writes message to the system message logger. The message is then written to the system console, log files, and logged-in users, or forwarded to other machines as appropriate. (See the syslogd command.)
The vsyslog() function is an alternate form in which the arguments have already been captured using the variable-length argument facilities of <stdarg.h>.
The message is tagged with priority. Priorities are encoded as a facility and a level. The facility describes the part of the system generating the message. The level is selected from the following list (ordered from high to low):
syslog(LOG_ALERT, "who: internal error 23"); openlog("ftpd", LOG_PID, LOG_DAEMON); setlogmask(LOG_UPTO(LOG_ERR)); syslog(LOG_INFO, "Connection from host %d", CallingHost); syslog(LOG_INFO|LOG_LOCAL2, "foobar error: %m");
POSIX 1003.1 XSI
closelog(), openlog(), setlogmask(), vsyslog()
logger, syslogd in the Utilities Reference