Character Generator

#include <stdio.h>#include <stdlib.h>#include <string.h>char *buffer;int spin(char* p,int length){        if(p>=buffer+length){                return 0;        }        /* 26 == alphabet */        for(*p='a';*p<'a'+26;*p+=1){                printf("%s\n",buffer);                /*Recursion*/                spin(p+1,length);        }        return 1;}/* * ./recurse <num_chars> * ./recurse 3 */int main(int argc, char ** argv) {        if(argc!=2) return argc;        int pass_length = atoi(argv[1]);        buffer = (char *) calloc(pass_length+1,sizeof(char));        buffer[pass_length]='\0';        memset(buffer,'a',pass_length);        /* This is a call to a recursive function */        spin(buffer,pass_length);        return 0;}