Why pointer to pointer?

Posted on 2008-10-16
Medium Priority
Last Modified: 2012-05-05
Hello group,

In a source file I was looking main() function is:

 int main(int argc, char **argv)

why there is **argv rather than *argv?

Question by:akohan
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LVL 53

Assisted Solution

Infinity08 earned 160 total points
ID: 22735601
>> why there is **argv rather than *argv?

Because that's how it's defined ;)

argv is an array of strings. A string is a char*. Multiple char*'s is char**, just like multiple int's is int*.
LVL 84

Assisted Solution

ozo earned 160 total points
ID: 22735603
so that it can point to a list of char *

Accepted Solution

RishadanPort earned 180 total points
ID: 22736178
The main idea that you have to understand, is that when you run a program, you may want to pass in a bunch of arguments.

Lets suppose you create a program, and which is named program.exe.

you can run the program like this:

program.exe <argument 0> <argument 1> <argument 2> <argument 3> ..

now in your main function you can access each of these arguments like this:

int main(int argc, char **argv){
   for(int index = 0; index < argc; index++){
      printf("Argument %d is: %s", index, argv[index]);   <-- (argv[index] is a char*)

Author Comment

ID: 22736451

Thanks to all specially for the details.


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