Files
Defects in how programs handle files: the mismatches between what the code assumes about a file’s state and what the operating system actually permits at the moment of the call. A file handle carries an implicit lifecycle — opened, read, written, closed — and most failures here come from acting out of step with it.
The entries group by the operation at fault. Reads and writes that move zero bytes betray confused length or buffer logic and accomplish nothing while masking the real intent; and state errors — using a handle that was never opened, or closing one twice — corrupt the descriptor’s lifecycle and lead to failed I/O, undefined behaviour, or use of a stale or recycled descriptor.