When using the integrated file system APIs, you can restrict access to objects as you can when using data management interfaces. Be aware, however, that adopting authorities is not supported. An integrated file system API uses the authority of the user profile under which the job is running.
Each file system may have its own special authority requirements. NFS server jobs are the only exception to this rule. Network File System server requests run under the profile of the user whose user identification (UID) number was received by the NFS server at the time of the request.
Authorities on your server are the equivalent of permissions on UNIX® systems. The types of permissions are read and write (for a file or a directory) and execute (for a file) or search (for a directory). The permissions are indicated by a set of permission bits, which make up the "mode of access" of the file or directory. You can change the permission bits by using the "change mode" functions chmod() or fchmod(). You can also use the umask() function to control which file permission bits are set each time a job creates a file.
For details on data security and authorities,
see the publication Security Reference 
.