[Info-vax] BASIC : Updating a sequential file causes run time error SIZRECINV (156)

[Paul Sture]

On 2016-06-03, Robert Nelson <26212714h at gmail.com> wrote:
>
>> User Action: Supply a valid COUNT value in the PUT or UPDATE statement
>> or a valid RECORDSIZE in the OPEN statement, whichever is applicable.
>
> Thanks Jan. I have already read up on this error. I believe I am
> specifying the new size in the UPDATE clause. As for RECORDSIZE in
> OPEN, the OPEN statement in the REFERENCE MANUAL states that BASIC
> retrieves the record size value from the file while opening existing
> files if not explicitly specified. 
>
> The file in question will have variable record lengths.
>

You cannot change the size of a record in a sequential file via an UPDATE.

Think about it:

o - if increasing the size, where does the extra space come from?
o - if decreasing the size, what happens to the remaining space? 

You can change the record size via an update with indexed files, but not
sequential ones.

-- 
There are two hard things in computer science, and they are cache invalidation,
naming, and off-by-one errors.