These constants are defined by the PHP core. This includes PHP, the Zend engine, and SAPI modules.
PHP_VERSION
(string)PHP_MAJOR_VERSION
(int)PHP_MINOR_VERSION
(int)PHP_RELEASE_VERSION
(int)PHP_VERSION_ID
(int)PHP_EXTRA_VERSION
(string)ZEND_THREAD_SAFE
(bool)ZEND_DEBUG_BUILD
(bool)PHP_ZTS
(bool) Alias ofZEND_THREAD_SAFE
PHP_DEBUG
(bool) Alias ofZEND_DEBUG_BUILD
DEBUG_BACKTRACE_PROVIDE_OBJECT
(int)DEBUG_BACKTRACE_IGNORE_ARGS
(int)PHP_MAXPATHLEN
(int)PHP_OS
(string)PHP_OS_FAMILY
(string)'Windows'
,'BSD'
,'Darwin'
,'Solaris'
,'Linux'
or'Unknown'
. Available as of PHP 7.2.0.PHP_SAPI
(string)PHP_EOL
(string)PHP_INT_MAX
(int)PHP_INT_MIN
(int)PHP_INT_SIZE
(int)PHP_FLOAT_DIG
(int)PHP_FLOAT_EPSILON
(float)x + 1.0 != 1.0
. Available as of PHP 7.2.0.PHP_FLOAT_MIN
(float)- PHP_FLOAT_MAX
. Available as of PHP 7.2.0.PHP_FLOAT_MAX
(float)DEFAULT_INCLUDE_PATH
(string)PEAR_INSTALL_DIR
(string)PEAR_EXTENSION_DIR
(string)PHP_EXTENSION_DIR
(string)PHP_PREFIX
(orPHP_PREFIX . "\\ext"
on Windows).PHP_PREFIX
(string)PHP_BINDIR
(string)PHP_SBINDIR
(string)PHP_BINARY
(string)PHP_MANDIR
(string)PHP_LIBDIR
(string)PHP_DATADIR
(string)PHP_SYSCONFDIR
(string)PHP_LOCALSTATEDIR
(string)PHP_CONFIG_FILE_PATH
(string)PHP_CONFIG_FILE_SCAN_DIR
(string)PHP_SHLIB_SUFFIX
(string)PHP_FD_SETSIZE
(int)E_ERROR
(int)E_WARNING
(int)E_PARSE
(int)E_NOTICE
(int)E_CORE_ERROR
(int)E_CORE_WARNING
(int)E_COMPILE_ERROR
(int)E_COMPILE_WARNING
(int)E_USER_ERROR
(int)E_USER_WARNING
(int)E_USER_NOTICE
(int)E_RECOVERABLE_ERROR
(int)E_DEPRECATED
(int)E_USER_DEPRECATED
(int)E_ALL
(int)E_STRICT
(int)__COMPILER_HALT_OFFSET__
(int)true
(bool)false
(bool)null
(null)PHP_WINDOWS_EVENT_CTRL_C
(int)PHP_WINDOWS_EVENT_CTRL_BREAK
(int)PHP_CLI_PROCESS_TITLE
(bool)STDERR
(resource)stderr
. Available only under the CLI SAPI.STDIN
(resource)stdin
. Available only under the CLI SAPI.STDOUT
(resource)stdout
. Available only under the CLI SAPI.See also:Magic constants.
All constants fromcore extensions are defined in PHP by default.