Beginning c++ and need help...

[Codiah]

So i'm beginning to learn C++ and i need to know how to get my new c++ program to run another program when its executed, and if its possible to get a c++ program to set a variable like the ones used in batch files.. %variablename%

really close to finishing my first project and any help would mean allot...

 

[Codiah]

I should rephrase all of this so its in context... anyway... heres the code..

#include <stdio.h>
#include <conio.h>
#include <string.h>
char User[21], Pwd[21];
#define UN "adminun"
#define PW "adminpw"
void MkAster();
void PromScr();
int main()


{
int att = 4;

printf("Please enter the following...\n");

for (; att >= 0; att--)


{
PromScr();

if (!stricmp(User, UN) && !strcmp(Pwd, PW))


{
printf("\nUsername and Password accepted!\n\n");
break;
}

else printf("\nInvalid Username or Password\n\nYou have %i attempts more.", att);
}
return 0;
}

void PromScr()


{
printf("\nUsername: "); scanf("%s", &User);
printf("Password: "); MkAster();
}

void MkAster()


{
int i = 0, geth = 0;


do {

geth = getch();
if(geth != 13)


{
if(geth == '\b')


{
if(i!= 0)


{
printf("\b \b");
Pwd = '\0';
i--;
}
}
else if(geth == '13') printf("\b \b");

else

{

Pwd = geth;
printf("*");
i++;
}
}
} while(geth != 13 );

Pwd = '\0';
}


What i want to do is set the password as a system variable when its entered, because i'm using it to verify the programs that follow... and i need to know how to once the password and username are entered, get it to run another program..

if i need to explain anything else just ask..

 

[mt2002]

A couple of suggestions...

>Dont mix C with C++ (You are doing this alot here);
>conio.h is nonstandard, dont use it;
>Use std::string over char buffers for storing strings. #include <string> (Note there is no *.h)

If you want to set it as a system variable, you should note this is OS dependent. In order to do this you will need to use the system API. Assuming Windows, it will be the Win32 API. I personally have not done it so cannot help you here.

i need to know how to get my new c++ program to run another program when its executed

This is (again) OS dependent. You can try the Win32 APIs ShellExecute() routine:

#include <windows.h>

//! execute someprogram.exe
ShellExecute (NULL, "open", "someprogram.exe", NULL, NULL, SW_SHOWNORMAL);

Probably the easiest way is running it from the system() routine though as it doesnt use the Win32 API:

#include <cstdlib>

//! execute someprogram.exe
std::system ("someprogram.exe");

Both are OS dependent. system() is ANSI C++ though.

 

[Codiah]

Well i certainly appreciate the feedback... but like i said i'm just learning C, so when it comes to terminology and right ways to do things i still come up rather short in most cases... so i guess i'm going to do a little research into this API thing for now... but again..
thanks...

 

[mt2002]

No worries I personally recommend staying clear of the Win32 application programming interface (API) for now until you get further into C++. The Win32 API is very large and complex and trying to learn it without having a good understanding of C can be hard.

 

[Codiah]

well on another note then, is there anything you could point me towards, i just started with C like two days ago... if maybe this isn't the greatest choice for beginners could you point me towards a programming language that is?

 

[Codiah]

Well, i'm just gonna start as basic as possible and work my way up.. i picked up a rather large book called, SAMS teach yourself C... hopefully it will get me on the right track... and i replace the conio in that program, changed it to iostream and updated my code, but it being put on the backburner till i learn a little more..

 

[mt2002]

That sounds like a good idea

Are you working with C or C++? They are quite different languages

 

[Codiah]

I've decided to start with C, figure i can easily expand from there later on if i want....