export - export variables to the environment of subsequently executed commands
export [OPTION] [NAME[=VALUE]...]
export sets the export attribute for the shell variables specified by NAMEs, or displays the list of names that are exported in this shell if no NAMEs are given. If a variable named by NAME does not exist, a new variable is created. If a variable name is followed by =VALUE, the value of the variable is set to VALUE.
Remove the export attribute from the named variables.
If -n option is specified and named variable does not exist, a new variable will not be created if NAME is not followed by a '=' character.