Oracle 7 sqlload and long raws

Have Oracle 7.0.16.4.0 on AIX

Attempting to load using sqlload a table with 12 columns, the first 11 being numbers,floats or chars and the last a long raw.

The Oracle manuals are Ok for loading "NORMAL" data but I cannot find much relating to loading long raws.

The long raw I am trying to load contains binary graphics data, so any delimiter for that field is out of the question. It is also variable in length (but always less that 64k).

What combination of load control parameters and load file format should I use to load the data.

Because the long raw is varable length and contains binary data the UNIX sqlload file processing options of FIX and STR cannot be used. The VAR option looks OK but it needs the record length in the first 5 chacters of the record. Is the length needed as character?
Does the length include itself?
Does the POSITION parameter of the control file start from the first byte of the length or the first byte of the actual data?

Many Thanks. John H......................................