Description

The C library function, The freopen() function first closes the file that may currently be associated with stream. However, if the attempt to close the file fails, the freopen( ) function still continues to open the other file.

Declaration

Following is the declaration for freopen() function

FILE *freopen(const char *filename, const char *mode, FILE *stream)

Parameters

filename - filename is a char pointer referencing the name of a file that you want to associate with the standard stream represented by stream.

mode - mode is another char pointer pointing to a string that defines the way to open a file. The values that mode can have in freopen() are the same as the mode values in the fopen() function.

Stream - The stream to associate with filename.

Return Value

The freopen( ) function returns a pointer to stream on success and a null pointer otherwise.

Example

#include <stdio.h>

int main ()
{
  freopen ("file.txt","w",stdout);
  printf ("This sentence is redirected.");
  fclose (stdout);
  return 0;
}

Output

This sentence is redirected.