IFS - FS Helper Functions

The following table summarizes the routines that make up the File System Helper interface between FSDs and the kernel. FSDs are loaded as dynamic link libraries and may import services provided by the kernel. These services can be called directly by the file system, passing the relevant parameters.

No validation of input parameters is done unless otherwise specified. The FSD calls FSH_PROBEBUF, where appropriate, before calling the FS help routine.

When any service returns an error code, the FSD must return to the caller as soon as possible and return the specific error code from the helper to the FS router.

There are many deadlocks that may occur as a result of operations issued by FSDs. OS/2 provides no means whereby deadlocks between file systems and applications can be detected.