Input/Output redirection

Everybody knows and uses output redirection to get the output of a command to a file.

With > you redirect STDOUT, with 2> you redirect STDERR and with &> you redirect both at the same time.

ls > output.txt
ls 2> error.txt
ls &> output_and_error.txt

But how do you get the output written to the screen AND to a file?

“tee” answers this question. This little program will accept text from STDIN and put in on STDOUT and write it to a file.
This is how you use it:

ls | tee output.txt

This entry was posted on Monday, February 26th, 2007 at 18:41 and is filed under Linux SysAdmin. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.

2 Comments

  1. DenRaf’s blog » Blog Archive » Terminal logging said:
    July 24th, 2007

    [...] tee. Explained here by my colleague raskas. This is nice, but you aren’t able to do manual [...]

  2. Raskas' blog ยป Input/Output redirection, appending said:
    August 15th, 2008

    [...] a previous post I wrote about output redirection of STDOUT, STDERR and both to a file. Off course you can do the [...]