Re: Q: IDL and endianness issues

["J.D. Smith" <jdsmith(at)astro.cornell.edu>]

Ossi Vaananen wrote:
> 
> Hi!
> 
> Let's say I have a binary file with known structure, and
> the file is written on a little-endian machine. Then I want
> to read it again on a big-endian machine. How do I do it?
> 
> If endianness was no problem, I could do this simply by
> creating a structure with contents that match the alignment
> of the different data types in the binary file, and then
> read data to it from the file with READU.
> 
> In Matlab, files can be opened with the endianness of the
> file explicitly given as an argument to fopen. In IDL manuals
> I saw no reference to such a feature in IDL.
> 
> The question is, does there exist a built-in feature in IDL
> that somehow allows endianness-specified file I/O?
> 

Take a look at byteorder() or swap_endian().  For best results, use the nasa
routines ieee_to_host and host_to_ieee.

Good luck,

JD

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