export
	export [-fn] [-p] [name[=value]]
	Mark each name to be passed to child processes in the environment. 
	If the -f option is supplied, the names refer to shell functions; 
	otherwise the names refer to shell variables. The -n option means 
	to no longer mark each name for export. If no names are supplied, 
	or if the -p option is given, a list of exported names is displayed.
	The -p option displays output in a form that may be reused as input. 
	If a variable name is followed by =value, the value of the variable 
	is set to value.

	The return status is zero unless an invalid option is supplied, 
	one of the names is not a valid shell variable name, 
	or -f is supplied with a name that is not a shell function.