| isfd | isam file identifier |
| int | key id number, where 1 represents the primary |
SUCCESS, or a negative value on error, in which case the error code is found in iserrno.
this routine checks the specified index for errors, and will return a value with the following bits set in accordance with it's findings:
IC_IDXREAD 3 index file read error IC_ORDER 4 key out of order IC_COUNT 5 index count mismatch IC_BADMAGIC 6 bad index node magic number
if the return value is zero then no errors were detected.