#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(void)
{
        char str[1024];

        while(1){
                fputs("$ ", stdout);
                fflush(stdout);
                if(fgets(str, sizeof str, stdin))
                {
                        char *dup = strdup(str);
                        char *cmd = strtok(dup, " \n");
                        char *param = strtok(NULL, " \n");

                        if(strcmp(cmd,"exit")==0)
                                exit(0);
                        else if(strcmp(cmd,"chdir")==0)
                                chdir(param);
                        else if(fork() == 0)
                        {
                                char *argv[64];
                                argv[0] = cmd;
                                argv[1] = param;

                                int i = 2;
                                while (argv[i-1] != NULL)
                                {
                                        argv[i] = strtok(NULL, " \n");
                                        i++;
                                }

                                execvp(cmd, argv);
                                printf(strcat(cmd,": not found\n"));
                                exit(0);
                        }
                        wait();
                }
        }
        return 0;
}