Skip to Main Content Search Help Tips Dictionary History Forums Contact You are here: Help > Linux and Unix About set Syntax Examples Related commands Linux and Unix main page set is a built-in function of the Bourne shell ( sh ), C shell ( csh ), and Korn shell ( ksh ), which is used to define and determine the values of the system environment . Bourne shell (sh): set [--aefhkntuvx[ argument ]]... C shell (csh): set [ var [= value ]] set var [ n ] = word Korn shell (ksh): set [+-aefhkmnopstuvx] [+-o option ]... [+-A name ] [ arg ...] In sh , the set built-in command has the following options: -- An option of a double-dash (" -- ") signifies the end of an option list. This is primarily useful when values listed after the options will start with a dash themselves. -a Mark variables which are modified or created for "export"; environmen...