PHP: error_log

(PHP 4, PHP 5)

error_log — Send an error message to the defined error handling routines

Description

bool error_log ( string $message [, int $message_type = 0 [, string $destination [, string $extra_headers ]]] )

Sends an error message to the web server's error log or to a file.

Parameters

message

The error message that should be logged.

message_type

Says where the error should go. The possible message types are as follows:

error_log() log types

0	message is sent to PHP's system logger, using the Operating System's system logging mechanism or a file, depending on what the error_log configuration directive is set to. This is the default option.
1	message is sent by email to the address in the destination parameter. This is the only message type where the fourth parameter, extra_headers is used.
2	No longer an option.
3	message is appended to the file destination. A newline is not automatically added to the end of the message string.
4	message is sent directly to the SAPI logging handler.

destination

The destination. Its meaning depends on the message_type parameter as described above.

extra_headers

The extra headers. It's used when the message_type parameter is set to 1. This message type uses the same internal function as mail() does.

Return Values

Returns TRUE on success or FALSE on failure.

Notes

Warning

error_log() is not binary safe. message will be truncated by null character.

Tip

message should not contain null character. Note that message may be sent to file, mail, syslog, etc. Use appropriate conversion/escape function, base64_encode(), rawurlencode() or addslashes() before calling error_log().

Email PHP errors instead of displaying it

By default, most servers are set to display an error message when an error occured in one of your script. For security reasons, you may want to get an email with the error, instead of displaying it to the public.

<?php

// Our custom error handler
function nettuts_error_handler($number, $message, $file, $line, $vars){
 $email = "
  <p>An error ($number) occurred on line
  <strong>$line</strong> and in the <strong>file: $file.</strong>
  <p> $message </p>";

 $email .= "<pre>" . print_r($vars, 1) . "</pre>";

 $headers = 'Content-type: text/html; charset=iso-8859-1' . "\r\n";

 // Email the error to someone...
 error_log($email, 1, 'you@youremail.com', $headers);

 // Make sure that you decide how to respond to errors (on the user's side)
 // Either echo an error message, or kill the entire project. Up to you...
 // The code below ensures that we only "die" if the error was more than
 // just a NOTICE.
 if ( ($number !== E_NOTICE) && ($number < 2048) ) {
  die("There was an error. Please try again later.");
 }
}

// We should use our custom function to handle errors.
set_error_handler('nettuts_error_handler');

// Trigger an error... (var doesn't exist)
echo $somevarthatdoesnotexist;