Compatibility: 1.0+
Expects: AH    22H
DS:DX address of an opened FCB
Returns: AL    0 if write was successful
1 if disk full error
2 if DTA + FCB recSize would overrun a segment (no write)
Info: Sets FCB curBlk and curRec to the agree with randomRec then
writes recSize bytes from the DTA to disk at the specified file

Notes:   Be sure to set recSize to the record length and randomRec in
the FCB to the desired record number.

See Also: Fn 40H (write file via handle)
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DOS Fn 22H: Write Random File Record