Proper format/standard of C program?

I've searched all over the internet looking for whats the most preferred format. I know C compilers don't care, but I want to make codes that look nice for others to edit, view over, etc. I guess its better to learn proper format from the beginning. I've learned C briefly about 2 years ago now I want to get back into it again. Please provide some links of known format/styles.

Here's an example of some of my code. Most of you probably know where this code came from. Notice how I spaced the variable from the equals, and bracket placements.

Code:

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#include <stdio.h>

/* print Fahrenheit-Celsius table
 * for fahr = 0, 20, ..., 300; floating-point version */
main()
{
        float fahr, celsius;
        float lower, upper, step;

        lower = 0;        /* lower limit of temperature scale */
        upper = 300;        /* upper limit */
        step = 20;        /* step size */

        fahr = lower;
        while (fahr <= upper) {
                celsius = (5.0/9.0) * (fahr-32.0);
                printf("%3.0f %6.2f\n", fahr, celsius);
                fahr = fahr + step;
        }
}

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There are a number of "coding standards" for C, which really means there is no one standard. Some popular ones, however, are listed here: Indent style - Wikipedia, the free encyclopedia.

I would say K&R, Allman and BSD KNF are the most popular, probably in that order. The example above is fine in terms of brace placement, spacing around operators, etc. Some people have highly religious views about indentation however. Whether to use tabs vs. spaces, whether you should indent 2, 4 or 8 characters (or some other number). Without sparking a tabs vs. spaces war, I will simply say that I find a 4-character indent most aesthetically pleasing, but 2 or 8 are fine as well.

The last note, always declare main to return an int, and put in a return statement before finishing main.

Quote:

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Originally Posted by anduril462

There are a number of "coding standards" for C, which really means there is no one standard. Some popular ones, however, are listed here: Indent style - Wikipedia, the free encyclopedia.

I would say K&R, Allman and BSD KNF are the most popular, probably in that order. The example above is fine in terms of brace placement, spacing around operators, etc. Some people have highly religious views about indentation however. Whether to use tabs vs. spaces, whether you should indent 2, 4 or 8 characters (or some other number). Without sparking a tabs vs. spaces war, I will simply say that I find a 4-character indent most aesthetically pleasing, but 2 or 8 are fine as well.

The last note, always declare main to return an int, and put in a return statement before finishing main.

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Thank you. I was looking for quite some time, I guess it never occurred to me to look up indent style.

The GNU indent tool works very well for the small C programs I have used it on. There is a windows version, too. It makes the indenting style moot, in my opinion. Just code in whatever style suits best. I prefer indent --line-length 90 -nut -brf -linux -i4

Code:

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#include <stdio.h>
/* Print command line arguments and exit. */
int main (int c, char **v){
    while (c--){
        printf ("Argument %i is \"%s\"\n",c,v[c]);
    }
    return 0;
}

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I misused flex to write a preprocessor to add missing or fix extra brackets and punctuation. I have no idea how to use flex and bison correctly, but that might be a benefit because my preprocessor does not understand C tokens (It just looks at indenting levels) so it works with other languages and scripts. To test the thing, I usually abuse it and code in a style like this, which is converted to the above style and compiled on the fly. With the tcc compiler, it also serves as sort of a scripting language that compiles C code and runs it in RAM. Though not as fast as code optimized with gcc, it is a lot faster than bash scripting :P:

Code:

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#!/usr/local/bin/anch -run
/* This will run as a bash script if TCC and Anchor is installed */

#include <stdio.h>
/* Print command line arguments and exit. */
int main  int c, char **v
    while  c--
        printf  "Argument %i is \"%s\"\n",c,v[c]
    return 0

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