Re: First C program

On 2014-04-02 02:32, frank kolmann wrote:

...
1. Don't use = in an if statement expression, unless it is
absolutely necessary.

Frank, this code seems to violate that guideline.

if ((pf = _Ropen(PFILENAME, "rr")) EQ NULL)
{ printf("can't open file %s\n", PFILENAME); exit(1); }

I think it's a very good guideline. I would code that like this. (I'll go along with the EQ ...)

pf = _Ropen(PFILENAME, "rr");
if (pf EQ NULL)
...

I would also spread out the code under the "if". I think it's too easy to miss the exit statement when the printf and exit are on the same line.
I also think it's easier to see exactly what code is conditioned by the "if" when the curly braces are coded on their own lines.

pf = _Ropen(PFILENAME, "rr");
if (pf EQ NULL)
{
printf("can't open file %s\n", PFILENAME);
exit(1);
}

This code takes up a few more lines than yours, but I find it much more readable-at-a-glance. If you want to collapse the code to make it easier to follow the whole program, you could put all the opens into a separate function.