Re: problems with char * return from a function

[Eus <eus at member dot fsf dot org>]

Hi Ho!

--- On Thu, 6/12/08, Vardhan, Sundara (GE Infra, Energy) <sundara.vardhan@ge.com> wrote:

> Hi All
>
> I am calling a function x within strcpy as follows
>
> strcpy(a,x("sample text","default text"));
>
> x is defined as follows
>
> char * x(char *m, char *n)
> {
>     char *return_val=NULL;
>     if (check m is in database)
>         return_val=m;
>     else
>         return_val=n;
>     return(return_val);
> }
>  This causes  the array a to have a corrupted string. The string is either m or n but with illegal characters appended.
> So I tried the following
> char *temp=NULL
> temp=x("sample text","default text");
> strcpy(a,temp);
>
>
> When I printed temp, it looked file, but when I printed a it was garbled. I had initialized as a[0]='\0';
>
> The same program works fine in Sun and IBM. Is there anything in GCC that I need to use as flag to have this not occur?
> Any help or pointers will be greatly appreciated.

It looks like that you have not zeroed your `a'.
`a[0]='\0';' is not enough.
Either you do `char a[BUFFER_SIZE] = {0};' when defining `a' or, better, you do `memset(a, 0, BUFFER_SIZE);'

> Thanks in advance

Your welcome.

> With Regards
>
> Vardhan

Best regards,
Eus