@node freopen, stdio
@subheading Syntax

@example
#include <stdio.h>

FILE *freopen(const char *filename, const char *mode, FILE *file);
@end example

@subheading Description

This function closes @var{file} if it was open, then opens a new
file like @code{fopen(filename, mode)} but it reuses @var{file}.

This is useful to, for example, associate @code{stdout} with a new file. 

@subheading Return Value

The new file, or @code{NULL} on error. 

@subheading Portability

@portability ansi, posix

@subheading Example

@example
freopen("/tmp/stdout.dat", "wb", stdout);
@end example