# Predefined Constants

It is possible to identify at runtime which `iconv` implementation is adopted by this extension.

`iconv` implementation constants
Name | Type | Description
--- | --- | ---
`ICONV_IMPL` | string | The implementation name
`ICONV_VERSION` | string | The implementation version

> Note:

> Writing implementation-dependent scripts with these constants is strongly discouraged.

The following constants are also available:

Other `iconv` constants
Name | Type | Description
--- | --- | ---
`ICONV_MIME_DECODE_STRICT` | int | A bitmask used for iconv_mime_decode()
`ICONV_MIME_DECODE_CONTINUE_ON_ERROR` | int | A bitmask used for iconv_mime_decode()