Thread: Bin Files

i need to know whats wrong with this code.... its out of the book im reading... and ... well it wont work for me...

Code:

#include <iostream.h>
#include <fstream.h>
using namespace std;

int get_int(int default_value);
char name[20];

int main() {
	char filename[81];
	int n;
	int age;
	int recsize = sizeof(name) + sizeof(int);

	cout<<"Enter file name: ";
	cin.getline(filename, 80);

	fstream fbin(filename, ios::binary | ios::init | ios::out);
	if (!fbin) {
		cout << "Could not open file " << filename;
		return -1;
	}

	cout << "Enter file record number: ";
	n = get_int(0);



	cout << "Enter name: ";
	cin.getline(name, 19);
	cout << "Enter age: ";
	age = get_int(0);

	fbin.seekp(n * recsize);
	fbin.write(name, 20);
	fbin.write(reinterpret_cast<char*>(&age),
		sizeof(int));
	fbin.close();
	return(0);
}


int get_int(int default_value) {
	char s[81];

	cin.getline(s, 80);
	if (strlen(s) == 0)
		return default_value;
	return atoi(s);
}

Code:

--------------------Configuration: Bin - Win32 Debug--------------------
Compiling...
Bin.cpp
D:\UFS\NETWORK PROGRAMMING\Bin\Bin.cpp(3) : error C2871: 'std' : does not exist or is not a namespace
D:\UFS\NETWORK PROGRAMMING\Bin\Bin.cpp(17) : error C2676: binary '|' : 'enum ios::open_mode' does not define this operator or a conversion to a type acceptable to the predefined operator
D:\UFS\NETWORK PROGRAMMING\Bin\Bin.cpp(46) : error C2065: 'strlen' : undeclared identifier
D:\UFS\NETWORK PROGRAMMING\Bin\Bin.cpp(48) : error C2065: 'atoi' : undeclared identifier
Error executing cl.exe.

Bin.exe - 4 error(s), 0 warning(s)

Originally Posted by PanzTec

D:\UFS\NETWORK PROGRAMMING\Bin\Bin.cpp(3) : error C2871: 'std' : does not exist or is not a namespace

This is due to the iostream.h/fstream.h vs iostream/fstream header issues mentioned in sigfriedmcwild's post.

Originally Posted by PanzTec

D:\UFS\NETWORK PROGRAMMING\Bin\Bin.cpp(46) : error C2065: 'strlen' : undeclared identifier

strlen is declared in the cstring header... so you will need to #include that one as well as the others.

Originally Posted by PanzTec

D:\UFS\NETWORK PROGRAMMING\Bin\Bin.cpp(48) : error C2065: 'atoi' : undeclared identifier

atoi would be declared in either the cstdlib or cmath headers so you would need to include one of those headers.

sweet!!! that almost worked
one last problom...

Code:

--------------------Configuration: Bin - Win32 Debug--------------------
Compiling...
Bin.cpp
d:\ufs\network programming\bin\bin.cpp(17) : error C2676: binary '|' : 'enum std::ios_base::_Openmode' does not define this operator or a conversion to a type acceptable to the predefined operator
Error executing cl.exe.

Bin.exe - 1 error(s), 0 warning(s)

This doesn't look like it's the cause of that error but I think you meant "ios::init" to be "ios::in". Aside from that it generates no errors with my Visual-I compiler [although I prefer using ios_base instead of ios and instead of checking `if (!fbin)' checking `if (!fbin.is_open())'].

Hello,

I believe LuckY pointed out the problem. Though, for future reference:

• Fstream constructor [mode]
• VC+ .Net 2003: Error C2676

- Stack Overflow

yeah he idi... now i feel really dumb... lol thanks lucky