Go Premium for a chance to win a PS4. Enter to Win

x
?
Solved

More file stuff

Posted on 2002-04-05
4
Medium Priority
?
230 Views
Last Modified: 2010-07-27
After using fseek() to locate parts of files, how can I get rid of them? (Directly from file)  Is there another function I can use?
Thank You!
0
Comment
Question by:pingle
  • 2
  • 2
4 Comments
 
LVL 86

Expert Comment

by:jkr
ID: 6921399
You mean, you wat to delete a section from a file? That's not possible. All you could do is "copying" the file while going through it and skipping the part you don't want...
0
 

Author Comment

by:pingle
ID: 6921434
Could you tell me how to do that?  That should serve my purpose just fine.
0
 
LVL 86

Accepted Solution

by:
jkr earned 200 total points
ID: 6921496
Well, if you had e.g. 6 records of the same size in a file and want to skip the 4th, you'd

#include <stdio.h>

struct RECORD {

 int i1;
 int i2;
 int i3;
 int i4;
};
void main () {

RECORD record;

 FILE* pIn = fopen ( "records.fil", "rb");
 FILE* pOut = fopen ( "new_records.fil", "wb");

 for ( int i = 0; i < 6; i++) {

   fread ( &record, sizeof ( RECORD), 1, pIn);

   if ( 3 == i) continue; // skip the 4th record at index 3

   fwrite ( &record, sizeof ( RECORD), 1, pOut);

 }

 fclose ( pIn);
 fclose ( pOut);
}

(error checking omitted for brevity)
0
 

Author Comment

by:pingle
ID: 6921540
Thank you AGAIN! I really appreciate it!
~Pingle
0

Featured Post

What does it mean to be "Always On"?

Is your cloud always on? With an Always On cloud you won't have to worry about downtime for maintenance or software application code updates, ensuring that your bottom line isn't affected.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Introduction This article is a continuation of the C/C++ Visual Studio Express debugger series. Part 1 provided a quick start guide in using the debugger. Part 2 focused on additional topics in breakpoints. As your assignments become a little more …
Article by: evilrix
Looking for a way to avoid searching through large data sets for data that doesn't exist? A Bloom Filter might be what you need. This data structure is a probabilistic filter that allows you to avoid unnecessary searches when you know the data defin…
The viewer will learn how to pass data into a function in C++. This is one step further in using functions. Instead of only printing text onto the console, the function will be able to perform calculations with argumentents given by the user.
The viewer will learn how to user default arguments when defining functions. This method of defining functions will be contrasted with the non-default-argument of defining functions.

877 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question