Returns the value of the configuration option on success. Failure, such as querying for a non-existant value, will return an empty string.
When querying boolean values: A boolean ini value of off will be returned as an empty string while a boolean ini value of on will be returned as "1".
When querying memory size values: Many ini memory size values, such as upload_max_filesize are stored in the .ini file in shorthand notation. ini_get() will return the exact string stored in the php.ini file, NOT its integer equivalent. Attempting normal arithmetic functions on these values will not have otherwise expected results.
<?php /* Our php.ini contains the following settings: display_errors = On register_globals = Off post_max_size = 8M */ print 'display_errors = ' . ini_get('display_errors') . "\n"; print 'register_globals = ' . ini_get('register_globals') . "\n"; print 'post_max_size = ' . ini_get('post_max_size') . "\n"; print 'post_max_size+1 = ' . (ini_get('post_max_size')+1) . "\n"; /* This script will produce: display_errors = 1 register_globals = post_max_size = 8M post_max_size+1 = 9 */ ?>
See also get_cfg_var(), ini_get_all(), ini_alter(), ini_restore(), and ini_set()