Pointer arithmetic on pointer of pointer (*argv[])?

I am aware that foo[bar] is equal to *(foo + bar), but what is *foo[bar] equal to, such as 开发者_开发问答accessing *argv[2]? I am somewhat confused in understanding this, I assumed maybe something like *(*(foo) + bar) but am unsure..

I apologize if this is a simple answer.

*a[b] is equivalent to *(a[b]) due to C and C++ precedence rules. so *a[b] is equivalent to **(a+b)

If the following are equivalent,

foo[bar]
*(foo + bar)

Then the following are equivalent too:

*foo[bar]
**(foo + bar)

It's my understanding that it is **(foo + bar)

Why?

*foo[bar] breaks down to * and foo[bar] since * is done after foo[bar] is dereferenced.

You already answered what foo[bar] == *(foo + bar)

Now add another * and you've got *(*(foo + bar))

Which also simplifies to **(foo + bar)

*foo[bar] is the pointer dereference to foo[bar].

Assuming a declaration of char *argv[], argv[2] refers to the third element of the argv array, which is a char *, and *argv[2] dereferences this pointer, giving you the first character in that string.