This statement causes all subsequent output, which is typically directed towards stdout, to go to the file FILE.TXT.
freopen( "file.txt", "w", stdout );
To return stdout to the display (the default stdout), use the following call:
In both of these cases, check the return value of freopen() to make sure that the redirection actually took place.
freopen( "CON", "w", stdout );
Below is a short program to demonstrate the redirection of stdout:
// Compile options needed: none
FILE *stream ;
if((stream = freopen("file.txt", "w", stdout)) == NULL)
printf("this is stdout output\n");
stream = freopen("CON", "w", stdout);
printf("And now back to the console once again\n");