syslog - send messages to the system logger Linux Man Page

NAME

closelog, openlog, syslog - send messages to the system logger

SYNOPSIS

#include <syslog.h>

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

void syslog(int priority , const char * format , ...);

void closelog(void);

#include <stdarg.h>

void vsyslog(int priority , const char * format , va_list ap );

DESCRIPTION

closelog()

openlog()

ident

option

openlog()

syslog() .

facility

syslog() .

option

facility

openlog()

syslog()

ident

syslog()

syslogd(8) .

priority

facility

level

format ,

printf(3)

format ,

strerror ( errno ).

vsyslog()

syslog()

stdarg(3)

PARAMETERS

option , " facility" ", and " priority .

option

openlog()

LOG_CONS: Write directly to system console if there is an error while sending to system logger.

LOG_NDELAY: Open the connection immediately (normally, the connection is opened when the first message is logged).

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.)

LOG_ODELAY: The converse of LOG_NDELAY ; opening of the connection is delayed until syslog() is called. (This is the default, and need not be specified.)

LOG_PERROR: (Not in SUSv3.) Print to stderr as well.

LOG_PID: Include PID with each message. facility The 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.

LOG_AUTH: security/authorization messages (DEPRECATED Use LOG_AUTHPRIV instead)

LOG_AUTHPRIV: security/authorization messages (private)

LOG_CRON: clock daemon

LOG_DAEMON: system daemons without separate facility value

LOG_FTP: ftp daemon

LOG_KERN: kernel messages

LOG_LOCAL0 " through " LOG_LOCAL7: reserved for local use

LOG_LPR: line printer subsystem

LOG_MAIL: mail subsystem

LOG_NEWS: USENET news subsystem

LOG_SYSLOG: messages generated internally by syslogd

LOG_USER " (default)": generic user-level messages

LOG_UUCP: UUCP subsystem
level This determines the importance of the message. The levels are, in order of decreasing importance:

LOG_EMERG: system is unusable

LOG_ALERT: action must be taken immediately

LOG_CRIT: critical conditions

LOG_ERR: error conditions

LOG_WARNING: warning conditions

LOG_NOTICE: normal, but significant, condition

LOG_INFO: informational message

LOG_DEBUG: debug-level message The function setlogmask(3) can be used to restrict logging to specified levels only.

CONFORMING TO

openlog() ,

closelog() ,

syslog()

vsyslog() )

LOG_USER

LOG_LOCAL*

facility .

LOG_AUTHPRIV

LOG_FTP ,

facility

LOG_PERROR

option

HISTORY

syslog

openlog (),

syslog (),

closelog (),

setlogmask ().

vsyslog ().

<varargs.h>

<stdarg.h> .

NOTES

ident

openlog()

syslog()

syslog(priority, "%s", string);