ini_restore

ini_get_all

Last updated: Fri, 27 Jun 2008

ini_get

(PHP 4, PHP 5)

ini_get — Gets the value of a configuration option

Description

string ini_get ( string $varname )

Returns the value of the configuration option on success.

Parameters

varname: The configuration option name.

Return Values

Returns the value of the configuration option as a string on success, or an empty string on failure or for null values.

Examples

Example #1 A few ini_get() examples


<?php
/*
Our php.ini contains the following settings:

display_errors = On
register_globals = Off
post_max_size = 8M
*/

echo 'display_errors = ' . ini_get('display_errors') . "\n";
echo 'register_globals = ' . ini_get('register_globals') . "\n";
echo 'post_max_size = ' . ini_get('post_max_size') . "\n";
echo 'post_max_size+1 = ' . (ini_get('post_max_size')+1) . "\n";
echo 'post_max_size in bytes = ' . return_bytes(ini_get('post_max_size'));

function return_bytes($val) {
    $val = trim($val);
    $last = strtolower($val[strlen($val)-1]);
    switch($last) {
        // The 'G' modifier is available since PHP 5.1.0
        case 'g':
            $val *= 1024;
        case 'm':
            $val *= 1024;
        case 'k':
            $val *= 1024;
    }

    return $val;
}

?>

The above example will output something similar to:


display_errors = 1
register_globals = 0
post_max_size = 8M
post_max_size+1 = 9
post_max_size in bytes = 8388608

Notes

Note: When querying boolean values A boolean ini value of off will be returned as an empty string or "0" while a boolean ini value of on will be returned as "1". The function can also return the literal string of INI value.

Note: When querying memory size values Many ini memory size values, such as upload_max_filesize, are stored in the php.ini file in shorthand notation. ini_get() will return the exact string stored in the php.ini file and NOT its integer equivalent. Attempting normal arithmetic functions on these values will not have otherwise expected results. The example above shows one way to convert shorthand notation into bytes, much like how the PHP source does it.


<?php

function get_upload_max_filesize()

{

    eval('return ' .

        str_replace(

            array('k','m','g'),

            array('*1024','*1048576','*1073741824'),

            strtolower(trim(ini_get('upload_max_filesize')))

        ) . ';'

    );

}

?>

khkjr at exple dot com
08-Oct-2007 10:43


This freakin conversion to bytes function does not work, nor does this one: ben at qolc dot net 22-Feb-2007 04:20

donations at bilawal dot co dot uk
01-May-2007 02:59


true, I'd use



<?php

$target="FUNC"; //INI_GET Target Function

if(!function_exists('ini_get'))

{

ini_get($target) or exit("Cannot collect ini_get() function");

}

?>

ben at qolc dot net
22-Feb-2007 10:20


Re Webmaster at Grimchild's code



As petrov says, grimchild's code doesn't "parse" the value, it just throws away the most significant part of it. Out of there you'll get a number but won't know whether it's bytes, kilobytes, megabytes or gigabytes! 



To parse the value you have to split off the character (if present) and multiply the number appropriately. Trivially:



<?php

$pms = ini_get('post_max_size');

if (preg_match('/^([\d\.]+)([gmk])?$/i', $pms, $m)) {

  $value = $m[1];

  if (isset($m[2])) {

    switch(strtolower($m[2])) {

      case 'g': $value *= 1024;  # fallthrough

      case 'm': $value *= 1024;  # fallthrough

      case 'k': $value *= 1024; break;

      default: die("Can't parse value '$pms' ");

    }

  }

  print "$value bytes\n";

} else {

  die("Can't parse value '$pms' ");

}

?>



Note the cunning or horrible (depending on your viewpoint) use of fallthrough between cases in the switch statement, so that for example 'g' gets multiplied by 1024 three times. If you ever write code which intentionally uses switch fallthrough like the above, be a good boy/girl and comment it, else someday it will come and bite you or your unfortunate cow-orkers.



It wouldn't surprise me if there's a PHP function to parse human-format sizes like this already (given that PHP itself has to do it).

petrov dot michael at gmail dot com
26-Sep-2006 02:40


@Webmaster at GrimChild dot com



Your suggestion to simply strip the [gmk] letters would actually be very unpredictable since you no longer know the magnitude of the number. Therefore if you have 8K and 8M they would be both equal after your function. Also the following would be incorrect:



<?php

// Incorrect code

function parse_size($size) {

    return eregi_replace('[gmk]','',$size);

}



//Check that we have at least 4M of post space

//      assume post_max_size = 16K

if(parse_size(ini_get('post_max_size')) < parse_size("4M")) {

      die('Error: this script requires more than 4M of post space');

}

?>



As you can see in this scenario the functions would return 16 and 4 respectively, allowing the check to succeed with less memory than 4M.

Webmaster at GrimChild dot com
20-May-2006 02:34


Just thought I would add.



Very simple way of parsing data such as post_max_size



eregi_replace('[gmk]','',ini_get('post_max_size'));

filh at filh dot org
21-Nov-2005 10:24


Concerning the value retourned, it depends on how you set it.

I had the problem with horde-3 which test the safe_mode value.

THan :

- if you set the value with php_admin_value safe_mode Off (or On) ini_get returns the string

- if you set the value with php_admin_flag safe_mode Off (or On) ini_get returns the boolean.

09-Nov-2005 05:56


@marcus at synchromedia dot co dot uk



you misunderstood the comment. Of course you can use on and off, and they will work correctly. 

But this entry is about *ini_get*. And if you ini_get() a value that is set to "off" in php.ini, you get returned 0 (as described above in the documentation). If you ini_get() a value that is set to "off" via .htaccess, you will be returned the string "off", which - if you use it in an if-clause, will be autoconverted to 1 (as is usual for strings).



So the problem is that which is returned by ini_get(), not what you can and cannot use in .htaccess. Sorry being unclear about this.

marcus at synchromedia dot co dot uk
05-Nov-2005 05:21


The last comment about setting values in .htaccess is not right. These lines both result in display_errors being turned off:



php_value display_errors true

php_value display_errors off



So PHP does NOT coerce the value into a boolean, but it checks for exact values of the string. These both work:



php_value display_errors on

php_value display_errors 1

01-Nov-2005 03:16


Important: The manual says that ini_get will return 0 or an empty string for boolean config values that are set to off in php.ini. 



This is technically correct, however when you use 



php_value register_globals off



in an .htaccess file, ini_get will return the string, which will "evaluate" to 1. So if you are using mod_php you have to check boolean config values against the strings (upper/lowercase etc.) anyhow or you will get wrong results.

david dot tulloh at infaze dot com dot au
22-Jun-2005 10:01


You can set custom entries in the ini file to provide globals such as database details.

However these must be retrieved with get_cfg_var, ini_get won't work.

Der Graph
17-Aug-2004 02:59


It might be useful for included scripts that include other files to extend the 'include_path' variable:



<?  ini_set('include_path',ini_get('include_path').':../includes:');  ?>



Sometimes, it may also be useful to store the current 'include_path' in a variable, overwrite it, include, and then restore the old 'include_path'.

fbeyer at <nospam>clickhand dot de
13-Aug-2002 10:29


If you want to test ini flags (eg. On/Off), I recommend to explicitly cast the value returned by ini_get() to boolean - it is cleaner as you only get true or false, not 0 or 1 or "" as described above.



<?php

    $register_globals = (bool) ini_get('register_gobals');

?>



C fans may of course also cast it to (int) to play with 0 and 1 - that's also cleaner to print().

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