Is it possible to redirect output to multiple devices?

Question

Is it possible to redirect output to multiple devices/files?

program.exe 1> output1.txt 1>output2.txt

This only produces output2.txt in Windows.

Answer 1

tee is a command that offers you the flexibility on *nix machines to redirect output to multiple files.

From the man page -

DESCRIPTION
     The tee utility copies standard input to standard output, 
making a copy in zero or more files.  The output is unbuffered.

On Windows, you can use something similar to this.

Answer 2

If you're using a Unix/Linux shell, or Cygwin on Windows, you can use tee to copy stdin to multiple output files:

program.exe | tee output1.txt >output2.txt

Not sure if there's a tee equivalent in native Windows cmd.exe.

Most shells, such as bash, let you combine stdout and stderr. Here's the syntax to merge stdout and stderr from program.exe and pipe it into tee. 2>&1 says to redirect the output of file descriptor 2 (stderr) to file descriptor 1 (stdout)

program.exe 2>&1 | tee output1.txt >output2.txt