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Why pointer to pointer?

Posted on 2008-10-16
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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?


Regards.
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Question by:akohan
4 Comments
 
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by:Infinity08
Infinity08 earned 40 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*.
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by:ozo
ozo earned 40 total points
ID: 22735603
so that it can point to a list of char *
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Accepted Solution

by:
RishadanPort earned 45 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*)
   }
}
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Author Comment

by:akohan
ID: 22736451


Thanks to all specially for the details.

Regards.
ak
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