Hello everybody,
I am writing this post because I've just finished my first C project after a long time. It is a clone of the UNIX wc (Word Count). Right now, the program can only compute the number of words and rows. I haven't implemented the flags like -l, -w etc that wc has.
Feel free to give me tips on how to write better C code and to become a better programmer
kooi•23m ago
Seems pretty good.
When I was at NASA, their C coding required everything to be explicit. So
`if(!w_cnt || !r_cnt)
return NULL_PTR;
`
was wrapped in real brackets.
I was also told not to use ternery operators.
But that's NASA specific things.
Another NASA specific thing was to declare all variables at the top of a function instead of scattering declarations throughout. I see you've put them after the argument checks, so actually I think that lives up to that spirit.
ButlerianJihad•6m ago
I suppose that you mean wrapping in curly-braces, for explicit syntax?
if (cond) {
return val;
}
Also, there is only one instance of ternary operator in ANSI C:
cond ? succ() : fail();
This ternary syntax does not appear in main.c
"NULL_PTR" is a rather bold choice for an integer error status. I see where it’s coming from. It’s not wrong, but there are conventions for naming things.
Unix exit value 0 should indicate success. Posix system calls always return 0 on success. ANSI C library calls as well. For user-defined functions, you don’t have access to the "errno" variable, so you do what you gotta do.
Speaking of exit values, it’s also a good convention to explicitly use "exit()" rather than "return()" from main(). It’s exactly the same result. I recommend a book on standard C programming. I haven’t seen any for 30 years.
kooi•21m ago
Also, for some reason the "standard" in C return values is 0 for success.
kooi•18m ago
Personally, I'd make the NULL_PTR error message a bit more specific. "Memory Error" is quite general. The real issue is that specific invalid arguments were passed in.
Now since this may live in it's own module and not be a public function, that could be fine. But if it's ever expanded, you'll want callers to know what specifically went wrong to help debugging.
emanueleoggiano•55m ago
kooi•23m ago
When I was at NASA, their C coding required everything to be explicit. So
`if(!w_cnt || !r_cnt) return NULL_PTR; `
was wrapped in real brackets.
I was also told not to use ternery operators. But that's NASA specific things.
Another NASA specific thing was to declare all variables at the top of a function instead of scattering declarations throughout. I see you've put them after the argument checks, so actually I think that lives up to that spirit.
ButlerianJihad•6m ago
"NULL_PTR" is a rather bold choice for an integer error status. I see where it’s coming from. It’s not wrong, but there are conventions for naming things.
Unix exit value 0 should indicate success. Posix system calls always return 0 on success. ANSI C library calls as well. For user-defined functions, you don’t have access to the "errno" variable, so you do what you gotta do.
Speaking of exit values, it’s also a good convention to explicitly use "exit()" rather than "return()" from main(). It’s exactly the same result. I recommend a book on standard C programming. I haven’t seen any for 30 years.
kooi•21m ago
kooi•18m ago
Now since this may live in it's own module and not be a public function, that could be fine. But if it's ever expanded, you'll want callers to know what specifically went wrong to help debugging.