[x2x3i5x]

Hi

I'm still learning C programming. But I'm trying to write a program that will compare two text files and then if the two files are different, then tell me where the differences are (like what line, paragraph, etc) and if possible, display the differences.

Using strcmp to compare two text files is easy. It's the other parts that I'd like to know how to be able to do...

My attempt below....

I'm trying to now compare two files, then have program pick up the strings, then if different, display what the strings are. At least, that's my logic if it works.

//compare two files, then report where the differences are.

#include "stdafx.h"
#include <stdio.h>
#include<string.h>

int main()
{
	char c1[1000], c2[1000];
	//char s1[1000], s2[1000];
	FILE *f1;
	FILE *f2;

	f1 = fopen ("output.txt", "r");
	f2 = fopen ("output_copy.txt", "r");

	fgets(c1, 1000, f1);
	fgets(c2, 1000, f2);

	printf("\n");
	
	while((fgets(c1,1000,f1)!= NULL) && (fgets(c2,1000,f2)!= NULL))
	{
		if(strcmp(c1, c2) != 0)
			printf("%s", c1);
			printf("%s", c2);
	}
	printf("\n");

	fclose(f1);
	fclose(f2);
	return 0;
}

Thanks in advance!!

[Aphex19]

Whats the problem? You dont seem to mention any problems with this code.

[x2x3i5x]

the first problem ... nothing is being printed, I thought it should work unless I made a coding error.

second, how to get the program to tell me where exactly the files differ?

[taylorc8]

EDIT: sorry, it's C programming. try looking up a page on C file IO ?
You're probably going to want to output the location of the C equivalent to the GET pointer in C++ file io. I don't think I have any C examples handy. Sorry, and merry christmas!

Does this help any?

hmm.. I think if you output the location of the pointer in the file stream as soon as a difference is found it will work, correct?
You can have this code.

#include "stdafx.h"
#include <windows.h>
#include <iostream>
using namespace std;
class Compare
{
private:
	HANDLE hfile1,hfile2;
	char * buffer;
	char * bufferF2;
public:
	BOOL rTestF1,rTestF2;
	DWORD readcF1,readcF2;
	Compare()
	{
	buffer=NULL,bufferF2=NULL;
	buffer=new char[1024];
	bufferF2=new char[1024];
	rTestF1=true;
	rTestF2=true;
	readcF1=1;
	readcF2=1;
	}
	~Compare()
	{
			//cout << "Object Destroyed. " << endl;
			delete [] buffer;
			delete [] bufferF2;
			CloseHandle(hfile1);
			CloseHandle(hfile2);
	}
	int Open(char * arg1,char* arg2)
	{
		hfile1=CreateFileA(arg1,GENERIC_READ,FILE_SHARE_READ,0,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,0);
		hfile2=CreateFileA(arg2,GENERIC_READ,FILE_SHARE_READ,0,OPEN_EXISTING,FILE_ATTRIBUTE_NORMAL,0);
		if(hfile1==INVALID_HANDLE_VALUE || hfile2==INVALID_HANDLE_VALUE)
		{
			cout << "Error code " << GetLastError() << endl;
			return 1;
		}
		else
			return 0;
	}

private:
	int Read()
	{
		rTestF1=ReadFile(hfile1,buffer,1024,&readcF1,0);
		rTestF2=ReadFile(hfile2,bufferF2,1024,&readcF2,0);
		if(rTestF1==0 || rTestF2==0 )
		{
			cout << "Error code " << GetLastError() << endl;
			return 1;
		}
		else
		{
			return 0;
		}
	}
public:
	int Cmp()
	{
		while(Read()==0 && readcF1!=0 && readcF2!=0)
		{
			for(unsigned long a=0;a<readcF1;a++)
		{
			if(buffer[a]!=bufferF2[a])
			{
				cout << "Files are not equal!\n";
				//~Compare();
				return 1;
			}
		}
		}
		cout << "Files are equal.\n";
		return 0;
	}
};

This post has been edited by taylorc8: 25 December 2009 - 01:38 AM

[x2x3i5x]

Thank you...

Here's what I did have ...

///compare two files, then report where the differences are.

#include "stdafx.h"
#include <stdio.h>
#include<string.h>

int main()
{
	char c1[1000], c2[1000];
	//char s1[1000], s2[1000];
	FILE *f1;
	FILE *f2;

	f1 = fopen ("output.txt", "r");
	f2 = fopen ("output_copy.txt", "r");

	fgets(c1, 1000, f1);
	fgets(c2, 1000, f2);


	
	printf("\n");
	
	while((fgets(c1,1000,f1)!= NULL) && (fgets(c2,1000,f2)!= NULL))
	{
		if(strcmp(c1, c2) != 0)
			puts(c1);
			printf("\n");
			puts(c2);
	}
	
	printf("\n");

	fclose(f1);
	fclose(f2);
	return 0;
}

1. It prints out string when they're not the same (At least that's what I want it to do, but it's not exactly doing it...)

This post has been edited by x2x3i5x: 29 December 2009 - 05:44 PM

[x2x3i5x]

Quote

1. 1. It prints out string when they're not the same (At least that's what I want it to do, but it's not exactly doing it...)

This is the problem I wanted to fix first, not the thing about the line count, because I was already getting somewhere closer. But thank you anyway for looking at the line count issue..

Instead of you writing out the code for me every time, I think it would be better if you helped me out with my code by giving suggestions or hints that may help me get where I wanted (or help me get better at programming). Somehow, I don't feel like having the code spoon fed to me every time, unless I was really stuck.

#include "stdafx.h"
#include <stdio.h>
#include<string.h>

int main()
{
	char c1[1000], c2[1000];
	//char s1[1000], s2[1000];
	FILE *f1;
	FILE *f2;

	f1 = fopen ("output.txt", "r");
	f2 = fopen ("output_copy.txt", "r");

	fgets(c1, 1000, f1);
	fgets(c2, 1000, f2);

	printf("\n");
	
	while((fgets(c1,1000,f1)!= NULL) && (fgets(c2,1000,f2)!= NULL))
	{
		if(strcmp(c1, c2) != 0)
			puts(c1);
			printf("\n");
			puts(c2);
	}
	
	printf("\n");

	fclose(f1);
	fclose(f2);
	return 0;
}

This post has been edited by x2x3i5x: 29 December 2009 - 09:50 PM

[x2x3i5x]

1.

Quote

You don't know in sytax

?

What is "in syntax"? Syntax for what ?

2. I meant, I'd like help improving my code to get what I would like to do, not you having to write a brand new code to do what I would like to do. Thank you for point out that fgets error, I missed it. But I forgot to remove the while loop, that's what should be deleted. The while loop got me nowhere.

3. Right now, the code prints out the string it read when it's different. But it prints out everything including the differences. So if one file has "Text Text" and the other has "Text Test", it'll print out everything.

Also Text Text is not being read the same Text
Text

So basically, I'd like the program to print out the the words that are different, regardless of where it is in the text files. Hope this makes sense?

Thanks for the help!!

This post has been edited by x2x3i5x: 30 December 2009 - 01:55 PM

[x2x3i5x]

...

This post has been edited by x2x3i5x: 30 December 2009 - 03:18 PM

[x2x3i5x]

Now, what would you do to store characters from a string read out of a text into an array?

I was thinking you have characters stored in an array pulled out of the strings read from the text (do the storing into the array when a difference is detected and then stop when it stops being different), then you could print out the characters one by one .... ?

This post has been edited by x2x3i5x: 30 December 2009 - 05:03 PM