pSOSystem System Calls - Read

pHILE+ System Calls verify_vol
verify_vol() examines the following volume control structures:
■ Root block
■ Bitmap
■ FLIST
■ All directories
■ All file indirect blocks
■ All file index blocks
verify_vol() stores a detailed description of the detected fault into a userprovided
fault descriptor block (FDB) and then calls the user-provided function
faultp(), described below.
faultp()
faultp() is called by verify_vol() without any parameters. faultp() is
responsible for additional processing of the fault.
verify_vol() calls faultp() with the following information:
■ The type of fault
■ A detailed description of the fault
■ An indication of whether or not the fault is correctable
faultp() performs its own check and returns a status code in the register
supported by pHILE+, which is processor-specific. The register used on each
processor family is specified in Target on page 2-128.
The status code faultp() returns must be one of the following:
Code Description
0 Continue volume verification without correcting the fault.
1 Correct fault and continue volume verification.
2 Terminate volume verification.
If status = 1 is returned, verify_vol() makes modifications to the volume, which
correct the fault. In most cases, the obvious modification is made. Less obvious
modifications are described in “Bad Blocks” on page 2-139. Note that status = 1
pSOSystem System Calls 2-131
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