Php/docs/function.error-log

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error_log

(PHP 4, PHP 5, PHP 7)

error_logSend an error message to the defined error handling routines


Description

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

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().


Examples

Example #1 error_log() examples

<?php// Send notification through the server log if we can not// connect to the database.if (!Ora_Logon($username, $password)) {    error_log("Oracle database not available!", 0);}// Notify administrator by email if we run out of FOOif (!($foo = allocate_new_foo())) {    error_log("Big trouble, we're all out of FOOs!", 1,               "[email protected]");}// another way to call error_log():error_log("You messed up!", 3, "/var/tmp/my-errors.log");?>