shell模拟程序

#include <iostream>
#include <sys/wait.h>
using namespace std;

int main()
{
        while (1)
        {
                char szCmd[300] = {0};

                cout << "shell>";
                cin.getline(szCmd, sizeof(szCmd) - 1);

                int nPid = fork();

                if (-1 == nPid)
                {
                        perror("fork()\n");
                        exit(EXIT_FAILURE);
                }
                else if (0 == nPid )//child process
                {
                        execlp(szCmd, NULL);

                        //if execlp return means: not execute right! then print err info
                        perror("execute child process failed!");
                        exit(0);
                }
                else //parent process
                {
                        int nState =0;
                        waitpid(nPid, &nState, NULL);
                        cout << "child procss return " << nState << endl;
                }

        }
}