C - initialization of pointers, asterisk position [duplicate]

Answer 1

Both work. I'd argue that #1 is clearer in general, but misleading in C and can lead to errors, e.g.:

type* var1, var2;

// This actually means:

type *var1;
type var2;

So I'd say that #2 is more idiomatic in C and therefore recommended, especially if you are not the only programmer working on the code (unless, of course, you all agree on a style).

Answer 2

The second mode is correct. The other mode are not so clear for a novice programmer. The form int* variable is usually discouraged

Answer 3

As others have pointed out, both work fine, and the wrong one actually has the advantage of syntactic economy.

The way I look at it, a declaration consists of type followed by the variable.

<type> <variable>;

int   ii;
int* pii;

So, if you take away the variable, what remains is the type. Which is int and int* above. The compiler treats int* as a type internally (which is pointer to an int).

C, unfortunately, does not support this syntax seamlessly. When declaring multiple variables of the same type, you should be able to do this:

<type> <variable>, <variable>, <variable>;

which you cannot with a pointer type:

int* ii1, ii2, ii3;

declares ii1 of type int* and the rest of type int. To avoid this, I make it a habit of declaring only one variable per line.