Re: Portable record length

On Thu, 2006-08-10 at 12:49 +0000, Dan Nagle wrote:
Hello,

Asbjørn L. Johansen wrote:

<snip a bunch>

A good suggestion, but I need to output to a direct access, unformatted
file. The header contains 16 and 32 bit integer and 32 bit floating
point values. The data is an array of either 32 or 64 bit floating point
values.

Direct access has fixed length records, so you will waste space
in the file with this approach. If this is acceptable, then alright.

This is not an issue as I have to conform to a format specification. The
240 byte header is part of the specification and the length of the data
area is not allowed to change between records.

When reading the file, how do you signal the record length?, or is it
known from other logic?

That's the problem I'm trying to solve in a portable way. I need a
portable way of getting the record length which lets me store 240 bytes
of header + N elements of either 32 or 64 bit floating point values in a
direct access unformatted file.

I hope this clarified the problem. :)
--
Asbjørn L. Johansen
asbjorjo@xxxxxxxxxxxx

.

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