> > Have a look at the gcc info pages:
> > 
> > $ info gcc "invoking gcc" "warning options"
> 
> Sure, I'm not stupid! 

  Sorry, didn't mean to offend you.

> I looked for ~10 minutes how to turn off the remaining 
> warnings, but I could not find it. The code is now correct, like I do want the 
> "%y" format specifier in the strftime() function, but the warning is wrong.

  One way to remove the warnings would be to use "%Y" in a separate strftime() call
  and then taking only the last two digits (characters) of that string.

  Something like:
old:
   strftime(str, sizeof(str), "%A, %d-%b-%y %H:%M:%S GMT", gmt);

new:
   strftime(str, sizeof(str), "%A, %d-%b-XX %H:%M:%S GMT", gmt);
   strftime(year, sizeof(year), "%Y", gmt);
   i=strstr(str,"XX"); /* find position of XX */
   if ( i+1 < sizeof(str) ) {
     str[i]  =year[3];
     str[i+1]=year[4];
   } else ...

  Somewhat cumbersome, but should work.  Maybe consider using the four 
  digit year directly, where possible.

  Gruss, Heiko