PHP Error Handlings

error_log

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

message_type

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.

eg:

<?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 FOO
if (!($foo = allocate_new_foo())) {
error_log("Big trouble, we're all out of FOOs!", 1,
"operator@example.com");
}

// another way to call error_log():
error_log("You messed up!", 3, "/var/tmp/my-errors.log");
?>

error_reporting:

<?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 FOO
if (!($foo = allocate_new_foo())) {
error_log("Big trouble, we're all out of FOOs!", 1,
"operator@example.com");
}

// another way to call error_log():
error_log("You messed up!", 3, "/var/tmp/my-errors.log");
?>