This header file defines prototypes for the low-level POSIX functions creat and open, and provides symbolic constants for the POSIX open mode flags (O_*). Neither creat nor open are defined in the minimal C library, but instead are defined in the POSIX library (see Section 17).The open mode constants defined by this header are identical to and interchangeable with the corresponding constants defined in oskit/fs/file.h for the oskit_file COM interface (see 9.4. These definitions are provided so that clients may standardize on a single set of defintions, which are the same as those used by the COM components. For example, the FreeBSD C library includes this header file, thus providing compatibility between the the two libraries and the disk-based file systems.