amount of data and decrease SKIP. Increment *TOTAL by the amount
of data written. If OUT2 is not NULL, also write BUF to OUT2.
In case of error writing to OUT, -1 is returned. In case of error
amount of data and decrease SKIP. Increment *TOTAL by the amount
of data written. If OUT2 is not NULL, also write BUF to OUT2.
In case of error writing to OUT, -1 is returned. In case of error