Question

write the commands to print out ones entry in /etc/passwd file in unix operating system.

Answer 1

Answer:

cut -d: -f1,3,4 /etc/passwd | tr ':' '\t'

Explanation:

An example of entries in the /etc/passwd file:

root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/bin/sh
bin:x:2:2:bin:/bin:/bin/sh
sys:x:3:3:sys:/dev:/bin/sh
sync:x:4:65534:sync:/bin:/bin/sync
games:x:5:60:games:/usr/games:/bin/sh

cut can deal with character separated lines in text files

The options for cut to work are:

1. -d: Using a colon as delimiter
2. -f1,3,4 - outputs fields 1,3,and 4. Cut uses 1-indexing

Now the output of cut -d: -f1,3,4 /etc/passwd would have colon-delimited fields

To eliminate that we can use the translate command : tr

So the output is passed through a pipe and operated upon the tr command which replaces the colon with tabs ('\t')