Controls how include files are treated.
#pragma syspath_once on | off | reset
If you enable this pragma, files called in #include <> and #include "" directives are treated as distinct, even if they refer to the same file.
This pragma does not correspond to any panel setting in the Language panel. To check this setting, use __option (syspath_once), described in Checking Pragma Settings. By default, this setting is enabled. For example, the same include file could reside in two distinct directories.