Re: Best practices for Error Handling in C

Thanks Simon,

So this is what I've ended up with:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <qusec.h>


typedef struct myEC
{
Qus_EC_t EC_Fixed;
char Exception_Data[1024];
} myEC_t;

static int myFunction(myEC_t pApiErrCd);

int main(void)
{
// Declare the nested error structure

myEC_t ApiErrCd;
ApiErrCd.EC_Fixed.Bytes_Provided = sizeof(ApiErrCd);
ApiErrCd.EC_Fixed.Bytes_Available = 0;
myFunction(ApiErrCd);
return 0;
}

int myFunction(myEC_t pApiErrCd)
{
int intTest;
intTest = pApiErrCd.EC_Fixed.Bytes_Provided;
return 0;
}


Per your advice, I've modified the code. Its much cleaner. Thanks again

Erick

On Mon, Sep 22, 2008 at 9:05 PM, Simon Coulter <shc@xxxxxxxxxxxxxxxxx> wrote:

On 23/09/2008, at 9:51 AM, Erick Garske wrote:

I have a nested typedef structure for myEC that contains the variable
portion of the execption data. I've hard coded this at 100, but I have
also seen the Exeption data defined as large as 32767. What is the
best why to define the exception data?

I use 1024. Reasoning is 1K is a nice round number. Rochester's
design of the error code structure is flawed because it should have a
size of exception data field. This has been corrected if you use
format ERRC0200 for the error code structure instead of format
ERRC0100. See the Error code parameter section of the Information
Centre.

1K has been sufficient for all my use of APIs.

Also, I have made the tyepdef Structure local to both main and
myFunction, so I believe that the compiler should define both
structures local to their functions.

What's the point of defining a typedef twice? It's a user-defined
type so define it once globally--preferably in an include-- and just
declare instances of it wherever you need it.

Any other comments would be greatly appreciated.

int myFunction(void * pApiErrCd)

should be

int myFunction(myErC_t * pApiErrCd)

otherwise you are lying to the compiler.

If you do that then you won't need this:

myEC_t * ApiErrCd;

and then you won't need this either:

ApiErrCd = pApiErrCd;

The compiler has already passed you a pointer to the structure so
just use it via the indirection operator. What is the point of
passing void*, declaring another pointer to myEC_t, and assigning the
passed pointer to the local pointer?

Regards,
Simon Coulter.
--------------------------------------------------------------------
FlyByNight Software OS/400, i5/OS Technical Specialists

http://www.flybynight.com.au/
Phone: +61 2 6657 8251 Mobile: +61 0411 091 400 /"\
Fax: +61 2 6657 8251 \ /
X
ASCII Ribbon campaign against HTML E-Mail / \
--------------------------------------------------------------------



--
This is the C programming iSeries / AS400 (C400-L) mailing list
To post a message email: C400-L@xxxxxxxxxxxx
To subscribe, unsubscribe, or change list options,
visit: http://lists.midrange.com/mailman/listinfo/c400-l
or email: C400-L-request@xxxxxxxxxxxx
Before posting, please take a moment to review the archives
at http://archive.midrange.com/c400-l.