对 main 的 argc argv有点困惑 写了实验代码

#include <stdlib.h>

#include <stdio.h>



int

main( int argc, char** argv )

{

        int i = 0;

        for ( ; i < argc; i++ )

        {

                printf( "argv[%d] is %s\n", i, argv[i] );

        }



        int arg_c = argc;

        char** arg_v = argv;



        arg_c--, arg_v++;

        while (arg_c > 0 && *arg_v[0] == '-') {

                while (*++arg_v[0])

                {

                        switch (*arg_v[0])

                        {       

                                case 'v':

                                        printf("v\n");

                                        break;

                                case 'q':

                                        printf("q\n");

                                        break;

                                case 'f':

                                        printf("f\n");

                                        break;

                                default:

                                        break;

                        }

                //argc--, av++;

                }

                arg_c--, arg_v++;

        }



        for ( i = 0 ; i < argc; i++ )

        {

                printf( "argv[%d] is %s\n", i, argv[i] );

        }

        printf( "size of 4 is %d and null is %d\n", sizeof(argv[4]), sizeof('\0'));



        exit(0);

}