Runtime Configuration

The behaviour of these functions is affected by
settings in php.ini.

For further details and definitions of the PHP_INI_* modes, see the
Where a
configuration setting may be set.

Here’s a short explanation of the configuration
directives.

error_reporting integer

Set the error reporting level. The parameter is
either an integer representing a bit field, or named constants. The
error_reporting levels and constants are described in Predefined Constants,
and in php.ini. To set at runtime, use
the error_reporting() function. See also
the display_errors directive.

PHP 5.3 or later, the default value is
E_ALL &
~E_NOTICE &
~E_STRICT &
~E_DEPRECATED. This setting does not
show E_NOTICE,
E_STRICT and
E_DEPRECATED level errors. You may
want to show them during development. Prior to PHP 5.3.0, the
default value is E_ALL &
~E_NOTICE &
~E_STRICT.

Note:

Enabling E_NOTICE
during development has some benefits. For debugging purposes:
NOTICE messages will warn you about possible bugs in your code. For
example, use of unassigned values is warned. It is extremely useful
to find typos and to save time for debugging. NOTICE messages will
warn you about bad style. For example, $arr[item] is
better to be written as $arr[‘item’] since PHP tries to
treat “item” as constant. If it is not a constant, PHP
assumes it is a string index for the array.

Note:

Prior to PHP 5.4.0
E_STRICT was not included within
E_ALL, so you would have to
explicitly enable this kind of error level in PHP < 5.4.0.
Enabling E_STRICT during development
has some benefits. STRICT messages provide suggestions that can
help ensure the best interoperability and forward compatibility of
your code. These messages may include things such as calling
non-static methods statically, defining properties in a compatible
class definition while defined in a used trait, and prior to PHP
5.3 some deprecated features would issue
E_STRICT errors such as assigning
objects by reference upon instantiation.

Note: PHP Constants
outside of PHP

Using PHP Constants outside of PHP, like in
httpd.conf, will have no useful meaning
so in such cases the integer values are required. And since
error levels will be added over time, the maximum value (for
E_ALL) will likely change. So in
place of E_ALL consider using a
larger value to cover all bit fields from now and well into the
future, a numeric value like 2147483647 (includes all
errors, not just E_ALL).

display_errors string

This determines whether errors should be printed to
the screen as part of the output or if they should be hidden from
the user.

Value “stderr” sends the errors to
stderr instead of stdout. The value is available
as of PHP 5.2.4. In earlier versions, this directive was of type
boolean.

Note:

This is a feature to support your development and
should never be used on production systems (e.g. systems connected
to the internet).

Note:

Although display_errors may be set at runtime (with
ini_set()), it won’t have any effect if the
script has fatal errors. This is because the desired runtime action
does not get executed.

display_startup_errors boolean

Even when display_errors is on, errors that occur
during PHP’s startup sequence are not displayed. It’s strongly
recommended to keep display_startup_errors off, except for
debugging.

log_errors
boolean

Tells whether script error messages should be
logged to the server’s error log or error_log. This option is thus server-specific.

Note:

You’re strongly advised to use error logging in
place of error displaying on production web sites.

log_errors_max_len integer

Set the maximum length of log_errors in bytes. In
error_log information about the source is added. The
default is 1024 and 0 allows to not apply any maximum length at
all. This length is applied to logged errors, displayed errors and
also to $php_errormsg, but not to explicitly
called functions such as error_log().

When an integer is used, the value is measured in
bytes. Shorthand notation, as described in this
FAQ, may also be used.

ignore_repeated_errors boolean

Do not log repeated messages. Repeated errors must
occur in the same file on the same line unless ignore_repeated_source is set true.

ignore_repeated_source boolean

Ignore source of message when ignoring repeated
messages. When this setting is On you will not log errors with
repeated messages from different files or sourcelines.

report_memleaks boolean

If this parameter is set to On (the default), this
parameter will show a report of memory leaks detected by the Zend
memory manager. This report will be send to stderr on Posix
platforms. On Windows, it will be send to the debugger using
OutputDebugString(), and can be viewed with tools like » DbgView. This parameter only has
effect in a debug build, and if error_reporting includes
E_WARNING in the allowed list.

track_errors boolean

If enabled, the last error message will always be
present in the variable $php_errormsg.

html_errors
boolean

If enabled, error messages will include HTML tags.
The format for HTML errors produces clickable messages that direct
the user to a page describing the error or function in causing the
error. These references are affected by docref_root and docref_ext.

If disabled, error message will be solely plain
text.

xmlrpc_errors boolean

If enabled, turns off normal error reporting and
formats errors as XML-RPC error message.

xmlrpc_error_number integer

Used as the value of the XML-RPC faultCode
element.

docref_root
string

The new error format contains a reference to a page
describing the error or function causing the error. In case of
manual pages you can download the manual in your language and set
this ini directive to the URL of your local copy. If your local
copy of the manual can be reached by “/manual/” you can
simply use docref_root=/manual/. Additional
you have to set docref_ext to match the fileextensions of your copy
docref_ext=.html.
It is possible to use external references. For example you can use
docref_root=http://manual/en/ or
docref_root="http://landonize.it/?how=url&theme=classic&filter=Landon
&url=http%3A%2F%2Fwww.php.net%2F"

Most of the time you want the docref_root value to
end with a slash “/”. But see the second example above
which does not have nor need it.

Note:

This is a feature to support your development since
it makes it easy to lookup a function description. However it
should never be used on production systems (e.g. systems connected
to the internet).

docref_ext
string

See docref_root.

Note:

The value of docref_ext must begin with a dot
“.”.

error_prepend_string string

String to output before an error message.

error_append_string string

String to output after an error message.

error_log
string

Name of the file where script errors should be
logged. The file should be writable by the web server’s user. If
the special value syslog is used, the errors are sent to
the system logger instead. On Unix, this means syslog(3) and on
Windows it means the event log. See also: syslog(). If this directive is not set,
errors are sent to the SAPI error logger. For example, it is an
error log in Apache or stderr in CLI. See also
error_log().

syslog.facility string

Specifies what type of program is logging the
message. Only effective if error_log is set to “syslog”.

syslog.filter string

Specifies the filter type to filter the logged
messages. Allowed characters are passed unmodified; all others are
written in their hexadecimal representation prefixed with
\x. There are three supported filter types:

• all
  – all characters
• no-ctrl
  – all characters except control
  characters
• ascii
  – all printable ASCII characters and
  NL

Only effective if error_log is set to “syslog”.

syslog.ident string

Specifies the ident string which is prepended to
every message. Only effective if error_log is set to “syslog”.