Why is Visual Studio doing this!?

[mattonfire]

There are no errors showing for this but for some reason just after I enter the integer from the `cin` the window closes ignoring my answer, which should determine if it says "No that isn't my fav number" or continue to a function.

Here is my code:

http://hastebin.com/rujakujuje.tex

Here is the output:

http://hastebin.com/atezutohum.tex

[Enderman]

you need to have

using namespace std;

at the top of your code

and

system("pause");

where you want it to stop 

 

http://www.cplusplus.com/forum/beginner/1873/

[trag1c]

Move the cin.get() function call to the line before the end of your main and it will halt closing the program so that you can view your input.

1 minute ago, Enderman said:

you need to have

using namespace std;

at the top of your code

and

system("pause");

where you want it to stop 

 

http://www.cplusplus.com/forum/beginner/1873/

He has using using namespace std; at the top of of his file just below the includes. Anything to do with system() should be avoided as it introduces many vulnerabilities to the application and system.

[Enderman]

14 minutes ago, trag1c said:

Move the cin.get() function call to the line before the end of your main and it will halt closing the program so that you can view your input.

He has using using namespace std; at the top of of his file just below the includes. Anything to do with system() should be avoided as it introduces many vulnerabilities to the application and system.

system pause just makes the window hold until you press any key

how is that a vulnerability

[trag1c]

13 minutes ago, Enderman said:

system pause just makes the window hold until you press any key

how is that a vulnerability

Because system() can be replaced with malicious code as its an external executable that is called. So someone could replace the pause exe with a malicious one and totally screw you or the user over. 

 

Edit: There also other reasons to not use system() that can be derived from the text above. Its resource heavy because you're opening another executable and waiting for it to return. You also may not execute the command you were intending to execute. 

[AlTech]

10 hours ago, trag1c said:

Because system() can be replaced with malicious code as its an external executable that is called. So someone could replace the pause exe with a malicious one and totally screw you or the user over. 

 

Edit: There also other reasons to not use system() that can be derived from the text above. Its resource heavy because you're opening another executable and waiting for it to return. You also may not execute the command you were intending to execute. 

This negates a lot of C++'s benefits. 

[trag1c]

1 hour ago, AluminiumTech said:

This negates a lot of C++'s benefits. 

I don't think so simply because there are much better methods of pausing execution of a program that take little to no effort to implement. One of those being cin::get. Or simply waiting for a OS message like WM_KEYDOWN in a looped Windows application that is without a console. From my 6 years of experience with C++ I have never had to rely on system() anyways so its not at all a hindrance. There also the issue of portability with system("pause") as well since thats a windows only command so by saving your self keystrokes you're also keeping code portable and safe. 

[Nineshadow]

3 hours ago, AluminiumTech said:

This negates a lot of C++'s benefits. 

What does C++ and its benefits have to do with system()?

Cons :

It's not portable. This works only on systems that have the PAUSE command at the system level, like DOS or Windows. But not Linux and most others...

It's a very expensive and resource heavy function call. It's like using a bulldozer to open your front door. It works, but the key is cleaner, easier, cheaper. What system() does is:

• suspend your program
• call the operating system
• open an operating system shell (relaunches the O/S in a sub-process)
• the O/S must now find the PAUSE command
• allocate the memory to execute the command
• execute the command and wait for a keystroke
• deallocate the memory
• exit the OS
• resume your program

There are much cleaner ways included in the language itself that make all this unnessesary.

[mattonfire]

Okay, so don't use system(), the cons are just too much.

23 hours ago, Enderman said:

snip

Yes, this works. Thank you. And from some initiative I fixed "Else" too, well it might be common sense for you but anyway cheers

[mattonfire]

8 hours ago, Nineshadow said:

What does C++ and its benefits have to do with system()?

Cons :

It's not portable. This works only on systems that have the PAUSE command at the system level, like DOS or Windows. But not Linux and most others...

It's a very expensive and resource heavy function call. It's like using a bulldozer to open your front door. It works, but the key is cleaner, easier, cheaper. What system() does is:

• suspend your program
• call the operating system
• open an operating system shell (relaunches the O/S in a sub-process)
• the O/S must now find the PAUSE command
• allocate the memory to execute the command
• execute the command and wait for a keystroke
• deallocate the memory
• exit the OS
• resume your program

There are much cleaner ways included in the language itself that make all this unnessesary.

For the OS con (system only works on DOS and Windows), if you compile C++ it turns into a exe file that can't be run from any other OS apart from Windows anyway. Or can you compile C++ into other's like .jar's and things.

[Hamosch]

15 minutes ago, mattonfire said:

For the OS con (system only works on DOS and Windows), if you compile C++ it turns into a exe file that can't be run from any other OS apart from Windows anyway. Or can you compile C++ into other's like .jar's and things.

You just compile the source for another OS, for example for Linux you usually use the GCC/g++ compiler. C/C++ are inherently not locked to any OS, that is introduced by the programmer using OS specific libraries and calls etc... 

[mattonfire]

Anyone know why forms is doing this as soon as I started up, before I even started editing?