dos prompt disappearing

I want to make a program similar to the dos prompt (i dont know the english name for it) in wich you can issue commands to your system (like 'netsat -n' or 'ping 127.0.0.1'). It works, but it should return to the main() function as soon as the command was executed. Instead, it closes. The code i have so far is:

Code:

#include <iostream.h>

char command[99999];

int main()
{
    cout << "Command>";
    cin.getline(command, 99999, '\n');
    system(command);
    int main();
    return 0;
}

could anyone pease tell me what`s wrong with the code?

FAQ > How do I... (Level 1) > Stop my Windows Console from disappearing everytime I run my program?

well to start off...you could use:

Code:

#include<iostream>
using namespace std;

Also, you can put char command[99999] at the begining of main. you can also use

Code:

cin >> command;

instead of

Code:

cin.getline(command, 99999, '\n');

You can also take out int main() inside main and replace by a do while or something. I think you can start with that.

edit: and then add what thantos said to the end

Well, ive tried making the user input quit to exit:

Code:

#include <iostream.h>
#include <string.h>

char command[99999];

int main()
{
    cout << "Command>";
    cin.getline(command, 99999, '\n');
    if(!strcmpi("quit", char command)
    {
        return 0;system(command);
        int main();
    }
    
    else
    {
        system(command);
        int main();
    }
}

But in Dev-cpp it gives me the errors:

parse error before `)' token

parse error before `else'

But i couldn`t find any missing semicolons, wrong letters, etc.

And using

Code:

cin << command

instead of using

Code:

cin.getline(command, 99999, '\n')

would make ping 127.0.0.1 to be read by the program as ping.

and what`s in the faq doesnt work

Actually whats in the faq does work
Heres a hint:

Code:

int main();

Is not a function call.

what version of dev do u use? I wasnt working for me so i upgraded to 4.9.9.0 (the 5 beta or whatever) and it worked

>>>>>You can also take out int main() inside main and replace by a do while or something.

Code:

if(!strcmpi("quit", char command)

1) missing a closing )
2) Can't declare a variable there

Try something like this:

Code:

#include <iostream>
#include <string>

int main()
{
    using namespace std;
    string command;
    for (;;)
    {
      cout << "Command>";
      getline(cin, command);
      if ( command == "quit")
        break;
      system(command);
    }
}

Well, i`ve tried this:

Code:

#include <iostream.h>

char command[99999];

void exec();
void call();

int main()
{
    void exec();
}

void exec()
{
    cout << "Command>";
    cin.getline(command, 99999, '\n');
    if(command = "quit")
    {
        return;
    }
    
    else
    {
        void call();    
    }
    
}

void call()
{
    system(command);
    void exec();
}

But it gives me the error:

"incompatible types in assignment of `const char[5]' to ` char[99999]'"

could somebody tell me what to do? If i use

Code:

if (!strcmpi("quit", command))
{
          return;
}

else
{
          void call();
}

doesn`t work

it closes right away when i open the program

follow the standards and we can help you better... you need the <cstring> header for strcmpi, or in the older standards, <string.h>...

and put cin.get(); everywhere it could possibly run off the end of main...

with your line

Code:

if(command = "quit")

and the error you get, try changing that '=' to a '==' and see if it works

he can't do that anyway - he was right in trying strcmpi()

Originally Posted by major_small

follow the standards and we can help you better... you need the <cstring> header for strcmpi, or in the older standards, <string.h>...

Well using the standard and strcmpi don't go together as the function is non standard.

Again I'll refer you to my posting using std::string instead of a character array. It won't do insenstive comparison but with a little work it can.

Edit: Just noticed one small mistake on the code in the std::string post but I can't edit that post.

Code:

system(command);

Should be

Code:

 system(command.c_str());

My apologies for that mistake

However if you are dead set on using a null terminated array of characters here is some advise:

Using a loop to keep things alive while the person is executing commands. If you wish to use functions to get the input use return values to determine if you should continue or not.

As to why your program fails:

Code:

#include <iostream.h>

New standard specifies that the header should be <iostream>

Code:

char command[99999];

Not invalid just not good practice to use global variables

Code:

void exec();
void call();

These are ok and act as a prototype for the functions

Code:

int main()
{

Still ok

Code:

    void exec();

And here we have a problem. You think this is a call but guess what? It isn't. Its acting as a prototype for exec. to make it a call just use exec();

Code:

}

void exec()
{
    cout << "Command>";
    cin.getline(command, 99999, '\n');

This is ok

Code:

    if(command = "quit")

Here you are trying to assign the const array of characters "quit" to the array command which isn't valid

Code:

    {
        return;
    }
    
    else
    {

This is ok

Code:

        void call();

Same as above, its a prototype not a call

Code:

    }
    
}

void call()
{
    system(command);

This is ok

Code:

    void exec();

Again a prototype not a call

Code:

}

This is ok