Thread: W+ file blues.

Code:

FILE *superFile = fopen("test.txt","w+");

Erases the contents of the file test.txt. Isn't this supposed to open the file, leaving it intact and still allowing you to read and write? If not, is there another way?

> leaving it intact and still allowing you to read and write?
No, that's what "a+" does

Thought a wrote to the end of the file.
I'll try a+.

> Thought a wrote to the end of the file.
It does (initially), if you want to write elsewhere, then you'll need to fseek to it first

it's not seeking to the beginning.

Code:

FILE *fp = fopen("a.txt","a+");
fseek(fp,0,SEEK_SET);
fputc('x',fp);
fclose(fp);

It still adds to the end

Odd, it works here - gcc version 3.0.3(DJGPP)

Code:

#include <stdio.h> 

int main ( ) {
  FILE *fp = fopen( "test.txt", "a+" );
  int ch;

  fseek( fp, 0, SEEK_SET );
  ch = fgetc(fp);
  printf( "Ch read=%c\n", ch );

  fseek( fp, 0, SEEK_SET );
  fputc('@',fp);
  printf( "Wrote @\n" );

  fseek( fp, 0, SEEK_SET );
  ch = fgetc(fp);
  printf( "Ch read=%c\n", ch );

  fclose( fp );

  return 0;
}

> a.exe
Ch read=H
Wrote @
Ch read=@

Huh. Dev-c++ sucks .

Maybe windows.h is ****ing it up?

>r+ - Open for reading and writing. The stream is positioned at the beginning of the file.

This one sounds like it would do the trick.