#include <iostream>
#include <unistd.h>   // getcwd, chdir
#include <stdio.h>    // perror
#include <string.h>  
#include <libgen.h>   //dirname
#include <stdlib.h>



using namespace std;

const int MAX_SIZE = 256;

int main() {
    char path[MAX_SIZE];
    string command,
           append;
    char * env;
    char * tmp;
    string  full,
            base, 
            dir;

    while (command != "EXIT") {
        cout << endl;
        // show the behavior of the environment variable
	env = getenv("PWD");
	if (NULL != env) {
	   cout << "PWD: " << env << endl;
	}
	cout << endl;

        if (NULL == getcwd(path,MAX_SIZE)) {
	   perror("getcwd");
	   return -1;
	} 

        full = path;

	tmp = strdup(path);
	if (NULL == tmp){
	    perror("Strdup");
	    return -1;
	}
	dir = dirname(tmp);
	free(tmp);

	base = basename(path);

	cout << "basename:  " << base << endl;
	cout << "directory: " << dir  << endl;
        cout << "full:      " << full << endl;
	cout << endl;
	cout << base <<" : ";
	cin >> command;

	if (command == "UP") {
	   if(-1 == chdir(dir.c_str())) {
	       perror("Up failed ");
   	   }
	} else if (command == "GO") {
	    cin >> append;

	    if(-1 == chdir(append.c_str())) {
	        perror("chdir");
	        cout << "Could not change to " << append << endl;
	    }
	} else if (command != "EXIT") {
	    cout << "Unknown command " << command << endl;
	}

    }	

    return 0;

}