#include <iostream>
#include <strstream>
#include <string>
#include <vector>
#include <unistd.h>
#include <sys/wait.h>
using namespace std;

char** getCommandLine();
void freeArgs(char**);

int main() {
  while (true) {
    char** args = getCommandLine();
    pid_t pid = fork();
    if (pid < 0) {
      cerr << "simpleShell: could not fork new process\n";
      exit(1);
    }
    else if (pid == 0) { // child
      execvp(args[0], args);
	  cerr << "simpleShell: exec failed\n";
    }
    else { // parent
      int status;
      waitpid(pid, &status, 0);
    }
    freeArgs(args);
  }
}

char** getCommandLine() {
  cout << "\n:-) ";
  string line;
  getline(cin, line);
  istrstream is(line.c_str());
  string x;
  vector<string> vs;
  while (is >> x)
    vs.push_back(x);
  int argc = vs.size();
  char** args = new char*[argc+1];
  for (int i = 0; i < argc; ++i) {
    args[i] = new char[vs[i].length() + 1];
    strcpy(args[i], vs[i].c_str());
  }		  
  args[argc] = NULL;
  return args;
}


void freeArgs(char** args) {
  if (args) 
    for (int i = 0; args[i]; i++)
      delete [] args[i];
  delete [] args;
}