writing string to binary file (c_str() not working)

[emc2pp]

Hello guys,

I am trying to write a list of strings to a binary file:

string ab, ac, ad;
ab = "fly";
ac = "above";
ad = "the_rainbow";
ofstream on;
on.open("thefile", ios::binary);
on.write(ab.c_str(), 3);
on.write(ac.c_str(), 5);
on.write(ad.c_str(), 11);
on.close();

The program compiles fine, but when I want to read it to see if it's correct:

char* ba, *bc, *bd;
ifstream in;
in.open("thefile", ios::binary);
ba= new char[3];
bc= new char[5];
bd= new char[11];
in.read(ba, 3);
in.read(bc, 5);
in.read(bd, 11);
cout<<ba<<endl;
cout<<bc<<endl;
cout<<bd<<endl;
in.close();

when I run it, I get the words but with strange characters at the end:
fly"*
above"*
the_rainbow"*

I am suspecting the c_str() being a const char* which creates the problem?
Any help would be welcome

Thank!

[Null]

You forgot to append NULL character, so cout prints garbage and your program might crash.

If you just want to print the strings, use cout.write():
cout .write(ba,3);

But I think it's better to write NULL characters to file:

string ab, ac, ad;
ab = "fly";
ac = "above";
ad = "the_rainbow";
ofstream on;
on.open("thefile", ios::binary);
on.write(ab.c_str(), 4); // +1 for null character
on.write(ac.c_str(), 6);
on.write(ad.c_str(), 12);
on.close();

//...
char* ba, *bc, *bd;
ifstream in;
in.open("thefile", ios::binary);
ba= new char[4]; // again 3 + one null character
bc= new char[6];
bd= new char[12];
in.read(ba, 4);
in.read(bc, 6);
in.read(bd, 12);
cout<<ba<<endl;
cout<<bc<<endl;
cout<<bd<<endl;
in.close();

[emc2pp]

thanks allot for your answer,
but now, if I want to convert back my ouput to a string, does string (ba) would give me ab?