Since the saplogin.ini file comprises the system access data it will thus automatically set the correct SAP system connections. Similarly as in Windows installations, you would point to the saplogon.ini file in the SAP GUI preferences (in Windows under »Options > SAP Logon > configurations«) as illustrated below. If you have numerous systems listed in a typical saplogon.ini file you usually want to leverage this to import such settings into your SAP GUI 7.3 Java.
Note Before You Start decide between SAP GUI 7.3 or 7.4 Java I researched the task and share my experience: there are principally two steps required to successfully install SAP GUI 7.3 for Java on macOS (10.12).
