HOWTO redirect output: STDOUT / STDERR
Examples:
output or stdout to screen
$ echo "test"
redirects stdout to afile.txt
$ echo "test" > afile.txt
- 0 is stdin.
- 1 is stdout.
- 2 is stderr.
also redirects stdout to afile.txt
$ echo "test" 1> afile.txt
redirect stderr to afile.txt
$ echo "test" 2> afile.txt
>&
is the syntax to redirect a stream to another file descriptor
redirect stdin to stderr
$ echo "test" 1>&2
# or
$ echo "test" >&2
..or vice versa:
$ echo "test" 2>&1
So, in short.. 2>
redirects STDERR to an (unspecified) file, appending &1
redirects STDERR to STDOUT