Re: what is the meaning of "char **option"?

Omats.Z wrote:

what is meaning os "char **option meet"?
I get a function like this:
__________________________________
int getchoice(char *greet, char *choices[])
{
int chosen = 0;
int selected;
char **option; // what is this line mean?

ptr-to-ptr-to-char

a pointer is typically implemented as an address so option will contain
the
address of a location that holds the address of a location of a char.

option is of type char**
*option is of type char* (ptr-to-char)
**option is of type char

do {
printf("Choice: %s\n", greet);
option = choices;

option now points at choices

while (*option) {

*option points to the first entry of the choices array, the loop
continues so
long as the entry is not NULL

printf("%s\n", *option);
option++;

this advances to the next entry in the array

}
selected = getchar();
option = choices;
while (*option) {
if (selected == *option[0]) {
chosen = 1;
break;
}
}
if (!chosen) {
printf("Incorrect choice, select again\n");
}
} while (!chosen);
return selected;
}
__________________________________

I know "char *option" is a pointer. But what is the ** mean? If i
delete one *, this function can't be compiled!
PS: i compile it by GCC 4 on ArchLinux

a good text book should explain all this

--
Nick Keighley

.

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