• Installing/Configuring
  • Runtime Configuration

  • Runtime Configuration
  • Runtime Configuration

    Runtime Configuration

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

    Errors and Logging Configuration
    Name Default Changeable Changelog
    error_reporting NULL PHP_INI_ALL  
    display_errors “1” PHP_INI_ALL  
    display_startup_errors “0” PHP_INI_ALL  
    log_errors “0” PHP_INI_ALL  
    log_errors_max_len “1024” PHP_INI_ALL  
    ignore_repeated_errors “0” PHP_INI_ALL  
    ignore_repeated_source “0” PHP_INI_ALL  
    report_memleaks “1” PHP_INI_ALL  
    track_errors “0” PHP_INI_ALL Deprecated as of PHP 7.2.0.
    html_errors “1” PHP_INI_ALL  
    xmlrpc_errors “0” PHP_INI_SYSTEM  
    xmlrpc_error_number “0” PHP_INI_ALL  
    docref_root “” PHP_INI_ALL  
    docref_ext “” PHP_INI_ALL  
    error_prepend_string NULL PHP_INI_ALL  
    error_append_string NULL PHP_INI_ALL  
    error_log NULL PHP_INI_ALL  
    syslog.facility “LOG_USER” PHP_INI_SYSTEM Available as of PHP 7.3.0.
    syslog.filter “no-ctrl” PHP_INI_ALL Available as of PHP 7.3.0.
    syslog.ident “php” PHP_INI_SYSTEM Available as of PHP 7.3.0.

    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

    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 &


    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.


    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


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


    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


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


    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
    , 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.


    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

    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


    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
    It is possible to use external references. For example you can use
    docref_root=http://manual/en/ or

    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.


    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).


    See docref_root.


    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.


    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

    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
    • ascii
      – all printable ASCII characters and

    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”.