coreutils: The who command
1
1 The ‘who’ Command
1 =================
1
1 The first program is the ‘who’ command. By itself, it generates a list
1 of the users who are currently logged in. Although I’m writing this on
1 a single-user system, we’ll pretend that several people are logged in:
1
1 $ who
1 ⊣ arnold console Jan 22 19:57
1 ⊣ miriam ttyp0 Jan 23 14:19(:0.0)
1 ⊣ bill ttyp1 Jan 21 09:32(:0.0)
1 ⊣ arnold ttyp2 Jan 23 20:48(:0.0)
1
1 Here, the ‘$’ is the usual shell prompt, at which I typed ‘who’.
1 There are three people logged in, and I am logged in twice. On
1 traditional Unix systems, user names are never more than eight
1 characters long. This little bit of trivia will be useful later. The
1 output of ‘who’ is nice, but the data is not all that exciting.
1