syslog

(PHP 4, PHP 5, PHP 7)

syslog — Generate a system log message

Description

syslog ( int $priority , string $message ) : bool

syslog() generates a log message that will be distributed by the system logger.

For information on setting up a user defined log handler, see the syslog.conf (5) Unix manual page. More information on the syslog facilities and option can be found in the man pages for syslog (3) on Unix machines.

Parameters

priority

priority is a combination of the facility and the level. Possible values are:

syslog() Priorities (in descending order)
Constant Description
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

message

The message to send, except that the two characters %m will be replaced by the error message string (strerror) corresponding to the present value of errno.

Return Values

Returns TRUE on success or FALSE on failure.

Examples

Example #1 Using syslog()

<?php
// open syslog, include the process ID and also send
// the log to standard error, and use a user defined
// logging mechanism
openlog("myScriptLog", LOG_PID | LOG_PERROR, LOG_LOCAL0);

// some code

if (authorized_client()) {
    // do something
} else {
    // unauthorized client!
    // log the attempt
    $access = date("Y/m/d H:i:s");
    syslog(LOG_WARNING, "Unauthorized client: $access {$_SERVER['REMOTE_ADDR']} ({$_SERVER['HTTP_USER_AGENT']})");
}

closelog();
?>

Notes

On Windows NT, the syslog service is emulated using the Event Log.

Note:

Use of LOG_LOCAL0 through LOG_LOCAL7 for the facility parameter of openlog() is not available in Windows.

See Also