title _MAX_ENV ms.date 11/04/2016 f1_keywords _MAX_ENV MAX_ENV helpviewer_keywords MAX_ENV constant _MAX_ENV constant ms.assetid 66f0683e-6132-4297-b99b-6940534898b5 _MAX_ENV The maximum permissible string length of an environmental variable. Syntax #include <stdio.h> See Also Environmental Constants Global Constants