ptr++[0] = x

[daktem21]

what it means?

*(ptr++) = x ??????

[S_M_A]

Increment ptr then assign *ptr the value of x

[Zaccheus]

Yes, but it assigns x to the location that ptr was pointing to before ptr had been incremented.

[S_M_A]

Huh, shouldn't parenthesis make incrementation go first?

[MikeAThon]

Sorry, Zaccheus, I didn't realize that you were not the OP
Yes, but it assigns x to the location that ptr was pointing to before ptr had been incremented.
That's the way it's supposed to work. The value of a postfix expression is the value of the operand before the increment is applied. After the postfix expression is evaluated, the operand is incremented. The purpose of the parenthesis is to indicate that the postfix operator works on ptr, and not the value pointed-to by ptr.

If you want to assign x to the location pointed-to by ptr after incrementation, then use a preincrement:

*(++ptr) = x;

Mike

PS: Why is this a network question??

[MikeAThon]

Increment ptr then assign *ptr the value of x
Disagree. As explained above, the expression means that *ptr gets the value of x, and then ptr is incremented.

Mike