Segfault on ifs?

[DigitalDragon]

Hi - I have a piece of code that is supposed to do a basic display of text files:

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

int main(int argc, char **argv)
{
	char buf[100];

	if(argc==0)
	{
		cerr << "ERROR: Not enough parameters" << endl;
		cerr << "Syntax: " << argv[0] << "[file1] [file2] ... [fileN]" << endl;
		exit(1);
	}

	for(int i=1;i<argc;i++)
	{
		ifstream ifs;
		ifs.open(argv[i], ios::in);
		if (ifs.fail())
		{
			cerr << argv[0] << ": " << argv[i] << " No such file or directory" << endl;
		}
		else while(!ifs.eof())
		{
			ifs >> buf;
			cout << buf;
		}
	}
	exit(0);
}

There are two issues with it, however.

1. the program ignores the whitespace of whatever textfile it reads

2. I get segmentation fault errors on a certain file I'm supposed to test it with.

Thanks!

[ne555]

1. ifs >> buf reads till it find an space or a line break, and the separator is ignored.
You may want to use

std::string buf;
getline( ifs, buf );

2. More info is requested.

Also

if(argc==0) //I'm not sure that this could happen
  cerr << "Syntax: " << argv[0]; //but if argc is 0, then you don't have anything in argv 

[DigitalDragon]

Thanks for the help - my output is still getting stripped of its whitespace, though - as in, I want to output the text file such that it retains all of the original whitespace of whatever was in the file.

[PanGalactic]

The reason your code segfaults is that your "certain file" almost certainly has input that will overrun your 100-byte buffer. One should not use stream operators with fixed size buffers. That C++ even allows it is a language defect IMO. Use read() with fixed size buffers.

[Bazzy]

What you want is unformatted input/output.
See
http://www.cplusplus.com/reference/iostream/istream/read/
http://www.cplusplus.com/reference/iostream/ostream/write/

[DigitalDragon]

Thanks, I changed it to such:

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

int main(int argc, char **argv)
{
	char buf[100];

	if(argc==0)
	{
		cerr << "ERROR: Not enough parameters" << endl;
		cerr << "Syntax: " << argv[0] << "[file1] [file2] ... [fileN]" << endl;
		exit(1);
	}

	for(int i=1;i<argc;i++)
	{
		ifstream ifs;
		ofstream ofs;
		ifs.open(argv[i], ios::in);
		if (ifs.fail())
		{
			cerr << argv[0] << ": " << argv[i] << " No such file or directory" << endl;
		}
		else while(!ifs.eof())
		{
			std:: string buf; 
			getline (ifs, buf);
			cout << buf;
		}
	}
	exit(0);
}

When output shows, however, I'm still getting all the text as one block without whitespace - would this be a cout problem?