3.1.4.1.3 Environment Name Parameters
pEnvironment: This parameter MUST either be NULL or a pointer to a string that specifies the environment name. For rules governing environment names and Windows behaviors, see section 2.2.4.4.
The individual method sections include the following parameter validation steps by reference:
If pEnvironment is NULL, use the local environment of the print server.
If pEnvironment is a pointer, verify that the string that is referenced by the pEnvironment parameter identifies an environment name that is supported on this server, and if that verification fails, return ERROR_INVALID_ENVIRONMENT.