How to redirect printf() to file and then back to console

Question

I am working on a project that requires me to have output from within a mini shell on my C program to output to a file. Using ./program > file.txt wi

Answer 1

You can use freopen.

freopen("desiredFileName", "w", stdout);

Once you are done, you can undo the reassignment like this:

freopen("/dev/stdout", "w", stdout);

on Unix/Linux systems. I'm not sure whether there is a portable way to revert back.

UPDATE

If possible, you can use fprintf instead of printf, providing either stdout or a handle to the desired file, as appropriate.