error_log (PHP 4, PHP 5)error_log — Send an error message somewhere说明 bool error_log ( string $message [, int $message_type [, string $destination [, string $extra_headers ]]] ) Sends an error message to the web server's error log, a TCP port or to a file. 参数message The error message that should be logged. message_type Says where the error should go. The possible message types are as follows: error_log() log types 0 message is sent to PHP's system logger, using the Operating System's system logging mechanism or a file, depending on what the error_log configuration directive is set to. This is the default option. 1 message is sent by email to the address in the destination parameter. This is the only message type where the fourth parameter, extra_headers is used. 2 message is sent through the PHP debugging connection. This option is only available if remote debugging has been enabled. In this case, the destination parameter specifies the host name or IP address and optionally, port number, of the socket receiving the debug information. This option is only available in PHP 3. 3 message is appended to the file destination . A newline is not automatically added to the end of the message string. destination The destination. Its meaning depends on the message_type parameter as described above. extra_headers The extra headers. It's used when the message_type parameter is set to 1. This message type uses the same internal function as mail() does. 返回值 如果成功则返回 TRUE，失败则返回 FALSE。 范例Example#1 error_log() examples<?php // Send notification through the server log if we can not // connect to the database. if (!Ora_Logon($username, $password)) { error_log("Oracle database not available!", 0); }// Notify administrator by email if we run out of FOO if (!($foo = allocate_new_foo())) { error_log("Big trouble, we're all out of FOOs!", 1, "[email protected]"); }// other ways of calling error_log(): error_log("You messed up!", 2, "127.0.0.1:7000"); error_log("You messed up!", 2, "loghost"); error_log("You messed up!", 3, "/var/tmp/my-errors.log"); ?> --------------------------------------------------------------------------------error_get_lasterror_reportingErrors and Logging PHP Manual User contributed notes: frank at booksku dot com 2006-11-03 07:28 Beware! If multiple scripts share the same log file, but run as different users, whichever script logs an error first owns the file, and calls to error_log() run as a different user will fail *silently*!Nothing more frustrating than trying to figure out why all your error_log calls aren't actually writing, than to find it was due to a *silent* permission denied error! p dot lhonorey at nospam-laposte dot net 2006-08-28 18:33 Hi !Another trick to post "HTML" mail body. Just add "Content-Type: text/html; charset=ISO-8859-1" into extra_header string. Of course you can set charset according to your country or Env or content.EG: Error_log("<html><h2>stuff</h2></html>",1,"[email protected]","subject :lunch\nContent-Type: text/html; charset=ISO-8859-1");Enjoy ! marques at displague dot com 2005-08-27 04:52 Beware the size of your custom error_log!Once it exceeds 2GB the function errors, ending your script at the error_log() line. I'm sure this differs from OS to OS, but I have seen it die writing to ext2 under modern Linux systems. mac at codegreene dot com 2005-08-09 00:33 When outputting to syslog, it uses the syslog() function, which limits its output to 500 characters. We have been able to send multi-line output to the log, but newlines appear to be replaced with a space in the output, and output is cut off at 500 characters.A simple workaround for long, multi-line output is something like this:$errlines = explode("\n",$errmsg); foreach ($errlines as $txt) { error_log($txt); } php at kennel17 dot NOSPAM dot co dot uk 2005-07-26 05:04 It appears that the system log = stderr if you are running PHP from the command line, and that often stderr = stdout. This means that if you are using a custom error to both display the error and log it to syslog, then a command-line user will see the same error reported twice. kazezb at nospam dot carleton dot edu 2005-07-22 01:39 It appears that error_log() only logs the first line of multi-line log messages. To log a multi-line message, either log each line individually or write the message to another file. franz at fholzinger dot com 2005-04-21 00:21 In the case of missing your entries in the error_log file: When you use error_log in a script that does not produce any output, which means that you cannot see anything during the execution of the script, and when you wonder why there are no error_log entries produced in your error_log file, the reasons can be: - you did not configure error_log output in php.ini - the script has a syntax error and did therefore not execute 2003-03-29 06:14 when using error_log to send email, not all elements of an extra_headers string are handled the same way. "From: " and "Reply-To: " header values will replace the default header values. "Subject: " header values won't: they are *added* to the mail header but don't replace the default, leading to mail messages with two Subject fields.<?phperror_log("sometext", 1, "[email protected]", "Subject: Foo\nFrom: [email protected]\n");?>---------------%<----------------------- To: [email protected] Envelope-to: [email protected] Date: Fri, 28 Mar 2003 13:29:02 -0500 From: [email protected] Subject: PHP error_log message Subject: Foo Delivery-date: Fri, 28 Mar 2003 13:29:03 -0500sometext ---------------%<---------------------quoth the docs: "This message type uses the same internal function as mail() does." mail() will also fail to set a Subject field based on extra_header data - instead it takes a seperate argument to specify a "Subject: " string.php v.4.2.3, SunOS 5.8 dan at mojavelinux dot com 2003-02-01 15:46 I find it very suprising that there are no PHP constants (or references to them if they exist) for the log types. I would expectSYSTEM_LOG = 0 TCP_LOG = 1 FILE_LOG = 2 MAIL_LOG = 3or something to that nature. Are we going to see this in any future versions? Seems very silly to use integers here when they could easily be changed or confused.
(PHP 4, PHP 5)error_log — Send an error message somewhere说明
bool error_log ( string $message [, int $message_type [, string $destination [, string $extra_headers ]]] )
Sends an error message to the web server's error log, a TCP port or to a file. 参数message
The error message that should be logged. message_type
Says where the error should go. The possible message types are as follows: error_log() log types 0 message is sent to PHP's system logger, using the Operating System's system logging mechanism or a file, depending on what the error_log configuration directive is set to. This is the default option.
1 message is sent by email to the address in the destination parameter. This is the only message type where the fourth parameter, extra_headers is used.
2 message is sent through the PHP debugging connection. This option is only available if remote debugging has been enabled. In this case, the destination parameter specifies the host name or IP address and optionally, port number, of the socket receiving the debug information. This option is only available in PHP 3.
3 message is appended to the file destination . A newline is not automatically added to the end of the message string.
destination
The destination. Its meaning depends on the message_type parameter as described above. extra_headers
The extra headers. It's used when the message_type parameter is set to 1. This message type uses the same internal function as mail() does.
返回值
如果成功则返回 TRUE，失败则返回 FALSE。 范例Example#1 error_log() examples<?php
// Send notification through the server log if we can not
// connect to the database.
if (!Ora_Logon($username, $password)) {
error_log("Oracle database not available!", 0);
}// Notify administrator by email if we run out of FOO
if (!($foo = allocate_new_foo())) {
error_log("Big trouble, we're all out of FOOs!", 1,
"[email protected]");
}// other ways of calling error_log():
error_log("You messed up!", 2, "127.0.0.1:7000");
error_log("You messed up!", 2, "loghost");
error_log("You messed up!", 3, "/var/tmp/my-errors.log");
?>
--------------------------------------------------------------------------------error_get_lasterror_reportingErrors and Logging
PHP Manual
User contributed notes:
frank at booksku dot com
2006-11-03 07:28
Beware! If multiple scripts share the same log file, but run as different users, whichever script logs an error first owns the file, and calls to error_log() run as a different user will fail *silently*!Nothing more frustrating than trying to figure out why all your error_log calls aren't actually writing, than to find it was due to a *silent* permission denied error!
p dot lhonorey at nospam-laposte dot net
2006-08-28 18:33
Hi !Another trick to post "HTML" mail body. Just add "Content-Type: text/html; charset=ISO-8859-1" into extra_header string. Of course you can set charset according to your country or Env or content.EG: Error_log("<html><h2>stuff</h2></html>",1,"[email protected]","subject :lunch\nContent-Type: text/html; charset=ISO-8859-1");Enjoy !
marques at displague dot com
2005-08-27 04:52
Beware the size of your custom error_log!Once it exceeds 2GB the function errors, ending your script at the error_log() line. I'm sure this differs from OS to OS, but I have seen it die writing to ext2 under modern Linux systems.
mac at codegreene dot com
2005-08-09 00:33
When outputting to syslog, it uses the syslog() function, which limits its output to 500 characters. We have been able to send multi-line output to the log, but newlines appear to be replaced with a space in the output, and output is cut off at 500 characters.A simple workaround for long, multi-line output is something like this:$errlines = explode("\n",$errmsg);
foreach ($errlines as $txt) { error_log($txt); }
php at kennel17 dot NOSPAM dot co dot uk
2005-07-26 05:04
It appears that the system log = stderr if you are running PHP from the command line, and that often stderr = stdout. This means that if you are using a custom error to both display the error and log it to syslog, then a command-line user will see the same error reported twice.
kazezb at nospam dot carleton dot edu
2005-07-22 01:39
It appears that error_log() only logs the first line of multi-line log messages. To log a multi-line message, either log each line individually or write the message to another file.
franz at fholzinger dot com
2005-04-21 00:21
In the case of missing your entries in the error_log file:
When you use error_log in a script that does not produce any output, which means that you cannot see anything during the execution of the script, and when you wonder why there are no error_log entries produced in your error_log file, the reasons can be:
- you did not configure error_log output in php.ini
- the script has a syntax error and did therefore not execute
2003-03-29 06:14
when using error_log to send email, not all elements of an extra_headers string are handled the same way. "From: " and "Reply-To: " header values will replace the default header values. "Subject: " header values won't: they are *added* to the mail header but don't replace the default, leading to mail messages with two Subject fields.<?phperror_log("sometext", 1, "[email protected]",
"Subject: Foo\nFrom: [email protected]\n");?>---------------%<-----------------------
To: [email protected]
Envelope-to: [email protected]
Date: Fri, 28 Mar 2003 13:29:02 -0500
From: [email protected]
Subject: PHP error_log message
Subject: Foo
Delivery-date: Fri, 28 Mar 2003 13:29:03 -0500sometext
---------------%<---------------------quoth the docs: "This message type uses the same internal function as mail() does." mail() will also fail to set a Subject field based on extra_header data - instead it takes a seperate argument to specify a "Subject: " string.php v.4.2.3, SunOS 5.8
dan at mojavelinux dot com
2003-02-01 15:46
I find it very suprising that there are no PHP constants (or references to them if they exist) for the log types. I would expectSYSTEM_LOG = 0
TCP_LOG = 1
FILE_LOG = 2
MAIL_LOG = 3or something to that nature. Are we going to see this in any future versions? Seems very silly to use integers here when they could easily be changed or confused.