File type and file mode values

Programming interface information

A mode value is input to z/OS UNIX chmod, open, creat, mkdir, and umask, and output by z/OS UNIX stat and fstat. The mode value is defined as a mode_t data type and consists of a one-byte file type and three bytes for the file modes. The file mode specifies the permission bits and the S_ISUID, S_ISGID, and S_ISVTX bits for a file.

End Programming interface information

Programming interface information

The z/OS UNIX macro BPXYMODE defines the mode_t values as:

Bits 0–7: file type, mapped by z/OS UNIX macro BPXYFTYP
Bits 8–13: reserved
Bits 14–31: available to the security product:
- Bits 14–19: reserved
- Bit 20: S_ISUID (set user ID on execution)
- Bit 21: S_ISGID (set group name on execution)
- Bit 22: S_ISVTX (keep loaded executable in storage)
- Bits 23–25: S_IRWXU (owner class mask)
  - Bit 23: S_IRUSR (read permission)
  - Bit 24: S_IWUSR (write permission)
  - Bit 25: S_IXUSR (search (if directory) or execute (otherwise) permission)
- Bits 26–28: S_IRWXG (group class mask)
  - Bit 26: S_IRGRP (read permission)
  - Bit 27: S_IWGRP (write permission)
  - Bit 28: S_IXGRP (search (if directory) or execute (otherwise) permission)
- Bits 29–31: S_IRWXO (other class mask)
  - Bit 29: S_IROTH (read permission)
  - Bit 30: S_IWOTH (write permission)
  - Bit 31: S_IXOTH (search (if directory) or execute (otherwise) permission)

End Programming interface information

Programming interface information

The system call services pass the mode parameter from the caller of the system call to the RACF® callable service or from the RACF callable service to the caller of the system call. The system call service can change the file type but does not change the file mode bits.

End Programming interface information

Programming interface information

Some RACF callable services test the file type to determine if the file is a directory. The makeFSP service sets the file type to "directory" if the file is a directory and sets it to zero otherwise.

End Programming interface information