Re: RPG prototype for C-language FILE *

[Scott Klement <rpg400-l@xxxxxxxxxxxxxxxx>]

Jay,

Here are the definitions I use for the fopen(), et al, APIs in RPG:
http://www.scottklement.com/rpg/copybooks/stdio_h.rpgle.txt

However, it might be worth noting that these APIs call the other ones 
(open() and friends) under the covers.  They add a layer of buffering on 
top of the standard IFS APIs, which can be useful...  but they aren't 
any better at handling "binary data".

I've never had an issue with open() and friends handling binary... 
works flawlessly, just don't add the O_TEXTDATA option.  (That option 
tells the API that it's text, not binary...)

With the fopen() APIs, I've had problems with binary data...  namely, if 
you use fgets, it seems to treat it as text, even if you specified the 
'b' flag on fopen().   This was not a problem if I used fread() instead. 
 And, this was a long time ago (10ish years ago) so it's possible that 
they already fixed it.  But, the point here, is that I've actually found 
binary works better with open() and friends vs. fopen().

If you're having trouble with not preserving the byte values of your 
file, I think it's likely that there's a bug in your code rather than 
the IFS APIs.

-SK



On 1/14/2016 7:16 AM, tegger@xxxxxxxxxxx wrote:
> Anyone come across a good prototype for C's FILE structure?
>
> I need to read/write binary files on the IFS and the standard open() isn't cutting it. The files are getting trashed. From my C-programming days, I know the fopen/fgetc/fputc/fclose process will do exactly what I need regardless of the nature of the file.
>
>
> Jay