About "fstream" in <fstream.h> and <fstream>

I run this is OK, "d.txt" is created and "12" is appended.

Code:

---

#include <fstream.h>

int main(){
        fstream file;
        file.open( "d.txt", ios::app );
                file.write( "12" ,2 );
        file.close();
        return 0;
}

---

But like this, there will be no effect.

Code:

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#include <fstream>

using namespace std;

int main(){
        fstream file;
        file.open( "d.txt", ios::app );
                file.write( "12" ,2 );
        file.close();
        return 0;
}

---

why? How to do if I must to write in the second form??
thx.

ios::app by itself is not a valid open mode. You need "ios::app | ios::out".

gg

Code:

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#include <fstream.h>

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If your compiler actually has this file its just for backwards compatibility.

Code:

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void main(){

---

main ALWAYS returns an int

Quote:

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Originally Posted by Thantos

Code:

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#include <fstream.h>

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If your compiler actually has this file its just for backwards compatibility.

Code:

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void main(){

---

main ALWAYS returns an int

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NO, sorry, i use "int main()" in normal times.

I wrote the "void main()" this time is for quick testing.

I correct it now.

thx

Quote:

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Originally Posted by Codeplug

ios::app by itself is not a valid open mode. You need "ios::app | ios::out".

gg

---

Still can not solve the problem. thx

I am using MS VC++ 6.

//==============================//

It is OK now ~~ sorry for bothering. THANKS . :p

>I am using MS VC++ 6.
Get a new compiler. Visual C++ 2005 Express is a free download, so you have no excuse.

>I wrote the "void main()" this time is for quick testing.
Get a better compiler and you'll be able to take advantage of the fact that main implicitly returns 0 if you fall off the end. Then using void main would actually take longer because void takes one more keystroke than int. You have no excuse for sloppy code, especially here.

>#include <fstream.h>
How this program works is strictly up to the compiler. The C++ standard says nothing about fstream.h, and you shouldn't be using it anyway.