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syslog(3C)		 Standard C Library Functions		    syslog(3C)

NAME
       syslog, openlog,	closelog, setlogmask - control system log

SYNOPSIS
       #include	<syslog.h>

       void openlog(const char *ident, int logopt, int facility);

       void syslog(int priority, const char *message, .../* arguments */);

       void closelog(void);

       int setlogmask(int maskpri);

DESCRIPTION
       The  syslog() function sends a message to syslogd(1M), which, depending
       on the configuration of /etc/syslog.conf, logs  it  in  an  appropriate
       system  log,  writes it to the system console, forwards it to a list of
       users, or forwards it to	syslogd	on another host	over the network.  The
       logged  message includes	a message header and a message body.  The mes-
       sage header consists of a facility indicator, a severity	level  indica-
       tor, a timestamp, a tag string, and optionally the process ID.

       The  message body is generated from the message and following arguments
       in the same manner as if	these were arguments to	 printf(3UCB),	except
       that  occurrences  of %m	in the format string pointed to	by the message
       argument	are replaced by	the error message string associated  with  the
       current	value  of  errno.   A  trailing	 NEWLINE character is added if
       needed.

       Values of the priority argument are formed by ORing together a severity
       level value and an optional facility value.
	If  no facility	value is specified, the	current	default	facility value
       is used.

       Possible	values of severity level include:

       LOG_EMERG
	     A panic condition.	 This is normally broadcast to all users.

       LOG_ALERT
	     A condition that should be	corrected immediately, such as a  cor-
	     rupted system database.

       LOG_CRIT
	     Critical conditions, such as hard device errors.

       LOG_ERR
	     Errors.

       LOG_WARNING
	     Warning messages.

       LOG_NOTICE
	     Conditions	 that  are  not	error conditions, but that may require
	     special handling.

       LOG_INFO
	     Informational messages.

       LOG_DEBUG
	     Messages that contain information normally	of use only  when  de-
	     bugging a program.

       The  facility  indicates	the application	or system component generating
       the message.  Possible facility values include:

       LOG_KERN
	     Messages generated	by the kernel. These cannot  be	 generated  by
	     any user processes.

       LOG_USER
	     Messages  generated by random user	processes. This	is the default
	     facility identifier if none is specified.

       LOG_MAIL
	     The mail system.

       LOG_DAEMON
	     System daemons, such as in.ftpd(1M).

       LOG_AUTH
	     The authorization system: login(1), su(1M), getty(1M).

       LOG_LPR
	     The line printer spooling system: lpr(1B),	lpc(1B).

       LOG_NEWS
	     Reserved for the USENET network news system.

       LOG_UUCP
	     Reserved for the UUCP system; it does not currently use syslog.

       LOG_CRON
	     The cron/at facility; crontab(1), at(1), cron(1M).

       LOG_LOCAL0
	     Reserved for local	use.

       LOG_LOCAL1
	     Reserved for local	use.

       LOG_LOCAL2
	     Reserved for local	use.

       LOG_LOCAL3
	     Reserved for local	use.

       LOG_LOCAL4
	     Reserved for local	use.

       LOG_LOCAL5
	     Reserved for local	use.

       LOG_LOCAL6
	     Reserved for local	use.

       LOG_LOCAL7
	     Reserved for local	use.

       The openlog() function sets process attributes that  affect  subsequent
       calls  to syslog(). The ident argument is a string that is prepended to
       every message.  The logopt argument indicates logging options.	Values
       for logopt are constructed by a bitwise-inclusive OR of zero or more of
       the following:

       LOG_PID
	     Log the process ID	with each message.
	      This is useful for identifying specific  daemon  processes  (for
	     daemons that fork).

       LOG_CONS
	     Write  messages  to  the system console if	they cannot be sent to
	     syslogd(1M). This option is safe to use in	daemon processes  that
	     have no controlling terminal, since syslog() forks	before opening
	     the console.

       LOG_NDELAY
	     Open the connection to  syslogd(1M)  immediately.	 Normally  the
	     open is delayed until the first message is	logged.	This is	useful
	     for programs that need to manage the order	in which file descrip-
	     tors are allocated.

       LOG_ODELAY
	     Delay open	until syslog() is called.

       LOG_NOWAIT
	     Do	not wait for child processes that have been forked to log mes-
	     sages onto	the console.  This option should be used by  processes
	     that  enable  notification	 of  child  termination	using SIGCHLD,
	     since syslog() may	otherwise block	waiting	for a child whose exit
	     status has	already	been collected.

       The  facility argument encodes a	default	facility to be assigned	to all
       messages	that do	not have an explicit facility  already	encoded.   The
       initial default facility	is LOG_USER.

       The  openlog()  and  syslog() functions may allocate a file descriptor.
       It is not necessary to call openlog() prior to calling syslog().

       The closelog() function closes any open file descriptors	 allocated  by
       previous	calls to openlog() or syslog().

       The  setlogmask()  function  sets the log priority mask for the current
       process to maskpri and returns the previous mask.  If the maskpri argu-
       ment  is	0, the current log mask	is not modified.  Calls	by the current
       process to syslog() with	a priority not set in  maskpri	are  rejected.
       The  mask  for  an  individual  priority	pri is calculated by the macro
       LOG_MASK(pri); the mask for all priorities up to	and  including	toppri
       is  given by the	macro LOG_UPT(toppri). The default log mask allows all
       priorities to be	logged.

       Symbolic	constants for use as values of the logopt, facility, priority,
       and maskpri arguments are defined in the	<syslog.h> header.

RETURN VALUES
       The  setlogmask()  function returns the previous	log priority mask. The
       closelog(), openlog() and syslog() functions return no value.

ERRORS
       No errors are defined.

EXAMPLES
       Example 1: Example of LOG_ALERT message.

       This call logs a	message	at priority LOG_ALERT:

       syslog(LOG_ALERT, "who: internal	error 23");

       The FTP daemon ftpd would make this call	to openlog() to	indicate  that
       all  messages it	logs should have an identifying	string of ftpd,	should
       be treated by syslogd(1M) as other messages from	 system	 daemons  are,
       should include the process ID of	the process logging the	message:

       openlog("ftpd", LOG_PID,	LOG_DAEMON);

       Then  it	would make the following call to setlogmask() to indicate that
       messages	at priorities from LOG_EMERG through LOG_ERR should be logged,
       but that	no messages at any other priority should be logged:

       setlogmask(LOG_UPTO(LOG_ERR));

       Then,  to log a message at priority LOG_INFO, it	would make the follow-
       ing call	to syslog:

       syslog(LOG_INFO,	"Connection from host %d", CallingHost);

       A locally-written utility could use the following call to  syslog()  to
       log  a  message	at  priority  LOG_INFO to be treated by	syslogd(1M) as
       other messages to the facility  LOG_LOCAL2 are:

       syslog(LOG_INFO|LOG_LOCAL2, "error: %m");

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO
       at(1), crontab(1), logger(1),  login(1),	 lpc(1B),  lpr(1B),  cron(1M),
       getty(1M),   in.ftpd(1M),   su(1M),   syslogd(1M),  printf(3UCB),  sys-
       log.conf(4), attributes(5)

SunOS 5.9			  29 Dec 1996			    syslog(3C)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | EXAMPLES | ATTRIBUTES | SEE ALSO

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