Someone writes:
> I've just been experimenting with message files (I'm on MPE 6.0)
>
> Is it the experience of all my friends on this list that if you
> build a message file
> thus :
>
> BUILD MSTEST;MSG;REC=-1000,,V,ASCII;DISC=10000
>
> that MPE pads your variable length writes to the file with spaces
> (or binary
> zeros if the file is defined as Binary rather than ascii) -
> effectively making
> this a fixed length file of 1000 bytes !

I believe that Message Files always store data in variable length format.
Message Files do have a "magic" feature that other file types don't however.
When you open a Message File you can specify either variable or fixed
records in the foptions and MPE will present the file as though it were a
fixed length file if you ask for fixed length records.  So essentially there
are two different views available for message files and the one you get
depends on the foptions that you specify (which you can do via :FILE
equations).

At least that's my recollection.

G.