+++ /dev/null
-.\" Written Feb 1994 by Steve Greenland (stevegr@neosoft.com)
-.\"
-.\" %%%LICENSE_START(VERBATIM)
-.\" Permission is granted to make and distribute verbatim copies of this
-.\" manual provided the copyright notice and this permission notice are
-.\" preserved on all copies.
-.\"
-.\" Permission is granted to copy and distribute modified versions of this
-.\" manual under the conditions for verbatim copying, provided that the
-.\" entire resulting derived work is distributed under the terms of a
-.\" permission notice identical to this one.
-.\"
-.\" Since the Linux kernel and libraries are constantly changing, this
-.\" manual page may be incorrect or out-of-date. The author(s) assume no
-.\" responsibility for errors or omissions, or for damages resulting from
-.\" the use of the information contained herein. The author(s) may not
-.\" have taken the same level of care in the production of this manual,
-.\" which is licensed free of charge, as they might when working
-.\" professionally.
-.\"
-.\" Formatted or processed versions of this manual, if unaccompanied by
-.\" the source, must acknowledge the copyright and authors of this work.
-.\" %%%LICENSE_END
-.\"
-.\" Updated 1999.12.19 by Karl M. Hegbloom <karlheg@debian.org>
-.\"
-.\" Updated 13 Oct 2001, Michael Kerrisk <mtk.manpages@gmail.com>
-.\" Added description of vsyslog
-.\" Added descriptions of LOG_ODELAY and LOG_NOWAIT
-.\" Added brief description of facility and option arguments
-.\" Added CONFORMING TO section
-.\" 2001-10-13, aeb, minor changes
-.\" Modified 13 Dec 2001, Martin Schulze <joey@infodrom.org>
-.\" Modified 3 Jan 2002, Michael Kerrisk <mtk.manpages@gmail.com>
-.\"
-.TH SYSLOG 3 2012-08-17 "Linux" "Linux Programmer's Manual"
-.SH NAME
-closelog, openlog, syslog, vsyslog \- send messages to the system logger
-.SH SYNOPSIS
-.B #include <syslog.h>
-.sp
-.BI "void openlog(const char *" ident ", int " option ", int " facility );
-.br
-.BI "void syslog(int " priority ", const char *" format ", ...);"
-.br
-.B "void closelog(void);"
-.sp
-.B #include <stdarg.h>
-.sp
-.BI "void vsyslog(int " priority ", const char *" format ", va_list " ap );
-.sp
-.in -4n
-Feature Test Macro Requirements for glibc (see
-.BR feature_test_macros (7)):
-.in
-.sp
-.BR vsyslog ():
-_BSD_SOURCE
-.SH DESCRIPTION
-.BR closelog ()
-closes the descriptor being used to write to the system logger.
-The use of
-.BR closelog ()
-is optional.
-.sp
-.BR openlog ()
-opens a connection to the system logger for a program.
-The string pointed to by
-.I ident
-is prepended to every message, and is typically set to the program name.
-If
-.I ident
-is NULL, the program name is used.
-(POSIX.1-2008 does not specify the behavior when
-.I ident
-is NULL.)
-
-The
-.I option
-argument specifies flags which control the operation of
-.BR openlog ()
-and subsequent calls to
-.BR syslog ().
-The
-.I facility
-argument establishes a default to be used if
-none is specified in subsequent calls to
-.BR syslog ().
-Values for
-.I option
-and
-.I facility
-are given below.
-The use of
-.BR openlog ()
-is optional; it will automatically be called by
-.BR syslog ()
-if necessary, in which case
-.I ident
-will default to NULL.
-.sp
-.BR syslog ()
-generates a log message, which will be distributed by
-.BR syslogd (8).
-The
-.I priority
-argument is formed by ORing the
-.I facility
-and the
-.I level
-values (explained below).
-The remaining arguments
-are a
-.IR format ,
-as in
-.BR printf (3)
-and any arguments required by the
-.IR format ,
-except that the two character sequence
-.B %m
-will be replaced by
-the error message string
-.IR strerror ( errno ).
-A trailing newline may be added if needed.
-
-The function
-.BR vsyslog ()
-performs the same task as
-.BR syslog ()
-with the difference that it takes a set of arguments which have
-been obtained using the
-.BR stdarg (3)
-variable argument list macros.
-
-The subsections below list the parameters used to set the values of
-.IR option , " facility" ", and " priority .
-.SS option
-The
-.I option
-argument to
-.BR openlog ()
-is an OR of any of these:
-.TP 15
-.B LOG_CONS
-Write directly to system console if there is an error while sending to
-system logger.
-.TP
-.B LOG_NDELAY
-Open the connection immediately (normally, the connection is opened when
-the first message is logged).
-.TP
-.B LOG_NOWAIT
-Don't wait for child processes that may have been created while logging
-the message.
-(The GNU C library does not create a child process, so this
-option has no effect on Linux.)
-.TP
-.B LOG_ODELAY
-The converse of
-.BR LOG_NDELAY ;
-opening of the connection is delayed until
-.BR syslog ()
-is called.
-(This is the default, and need not be specified.)
-.TP
-.B LOG_PERROR
-(Not in POSIX.1-2001 or POSIX.1-2008.)
-Print to \fIstderr\fP as well.
-.TP
-.B LOG_PID
-Include PID with each message.
-.SS facility
-The
-.I facility
-argument is used to specify what type of program is logging the message.
-This lets the configuration file specify that messages from different
-facilities will be handled differently.
-.TP 15
-.B LOG_AUTH
-security/authorization messages
-.TP
-.B LOG_AUTHPRIV
-security/authorization messages (private)
-.TP
-.B LOG_CRON
-clock daemon
-.RB ( cron " and " at )
-.TP
-.B LOG_DAEMON
-system daemons without separate facility value
-.TP
-.B LOG_FTP
-ftp daemon
-.TP
-.B LOG_KERN
-kernel messages (these can't be generated from user processes)
-.\" LOG_KERN has the value 0; if used as a facility, zero translates to:
-.\" "use the default facility".
-.TP
-.BR LOG_LOCAL0 " through " LOG_LOCAL7
-reserved for local use
-.TP
-.B LOG_LPR
-line printer subsystem
-.TP
-.B LOG_MAIL
-mail subsystem
-.TP
-.B LOG_NEWS
-USENET news subsystem
-.TP
-.B LOG_SYSLOG
-messages generated internally by
-.BR syslogd (8)
-.TP
-.BR LOG_USER " (default)"
-generic user-level messages
-.TP
-.B LOG_UUCP
-UUCP subsystem
-.SS level
-This determines the importance of the message.
-The levels are, in order of decreasing importance:
-.TP 15
-.B LOG_EMERG
-system is unusable
-.TP
-.B LOG_ALERT
-action must be taken immediately
-.TP
-.B LOG_CRIT
-critical conditions
-.TP
-.B LOG_ERR
-error conditions
-.TP
-.B LOG_WARNING
-warning conditions
-.TP
-.B LOG_NOTICE
-normal, but significant, condition
-.TP
-.B LOG_INFO
-informational message
-.TP
-.B LOG_DEBUG
-debug-level message
-.LP
-The function
-.BR setlogmask (3)
-can be used to restrict logging to specified levels only.
-.SH CONFORMING TO
-The functions
-.BR openlog (),
-.BR closelog (),
-and
-.BR syslog ()
-(but not
-.BR vsyslog ())
-are specified in SUSv2, POSIX.1-2001, and POSIX.1-2008.
-POSIX.1-2001 specifies only the
-.B LOG_USER
-and
-.B LOG_LOCAL*
-values for
-.IR facility .
-However, with the exception of
-.B LOG_AUTHPRIV
-and
-.BR LOG_FTP ,
-the other
-.I facility
-values appear on most UNIX systems.
-The
-.B LOG_PERROR
-value for
-.I option
-is not specified by POSIX.1-2001 or POSIX.1-2008, but is available
-in most versions of UNIX.
-.\" .SH HISTORY
-.\" A
-.\" .BR syslog ()
-.\" function call appeared in 4.2BSD.
-.\" 4.3BSD documents
-.\" .BR openlog (),
-.\" .BR syslog (),
-.\" .BR closelog (),
-.\" and
-.\" .BR setlogmask ().
-.\" 4.3BSD-Reno also documents
-.\" .BR vsyslog ().
-.\" Of course early v* functions used the
-.\" .I <varargs.h>
-.\" mechanism, which is not compatible with
-.\" .IR <stdarg.h> .
-.SH NOTES
-The argument
-.I ident
-in the call of
-.BR openlog ()
-is probably stored as-is.
-Thus, if the string it points to
-is changed,
-.BR syslog ()
-may start prepending the changed string, and if the string
-it points to ceases to exist, the results are undefined.
-Most portable is to use a string constant.
-.LP
-Never pass a string with user-supplied data as a format,
-use the following instead:
-.nf
-
- syslog(priority, "%s", string);
-.fi
-.SH SEE ALSO
-.BR logger (1),
-.BR setlogmask (3),
-.BR syslog.conf (5),
-.BR syslogd (8)
-.SH COLOPHON
-This page is part of release 3.79 of the Linux
-.I man-pages
-project.
-A description of the project,
-information about reporting bugs,
-and the latest version of this page,
-can be found at
-\%http://www.kernel.org/doc/man\-pages/.
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