When you use the creat() API to create a stream file, you can specify the data authorities for the owner, the primary group, and public (using the UNIX-like authorities of *R, *W, and *X).
The system uses the information in the parent directory to set the object authorities for the owner, primary group, and public. You can also specify these authorities when you use the open() API to create a stream file. Alternatively, when you use the open() API you can specify that the object should inherit all authorities from the parent directory. This is called inherit mode. When you specify inherit mode, the system then creates a complete match for the parent authorities, including authorization list, primary group, public authority, and private authorities. This option works like specifying *INDIR on the CRTDIR command.