This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these template messages)(Learn how and when to remove this template message)
$ echo -e "foo\tbar" | expand | xxd -g 1 -u 0000000: 66 6F 6F 20 20 20 20 20 62 61 72 0A foo bar. $ echo -e "foo\tbar" | xxd -g 1 -u 0000000: 66 6F 6F 09 62 61 72 0A foo.bar. $
Here the echo command prints a string of text that includes a tab character, then the output is directed into the expand command. The resulting output is then displayed in hexadecimal and as characters by the xxd dump command. At the second prompt, the same echo output is sent directly to the xxd command. As can be seen by comparing the two, the expand program converts the tab (specified as '\t' to the echo program) into spaces.