Self-Learned UNIX

    [sufficient] "finger sufficient" tells me (amongst other things)
                 "Never logged in." which seems a bit disingenuous given
                 I have to be logged in to see that.

So I cannot reproduce this,

    sdf$ finger thrig
    Login: thrig ...
    ...
    On since ...

though some poking around indicates that "finger" may not actually be the binary one might expect by default,

    sdf$ which finger
    /usr/pkg/bin/finger
    sdf$ finger | sed 1q
    finger-real: /dev//pts/123: No such file or directory
    finger-real: /dev//pts/146: No such file or directory
    Login    Name                Tty      Idle  Login Time   Office     Office Phone
    sdf$ file `which finger`
    /usr/pkg/bin/finger: Korn shell script, ASCII text executable
    sdf$ less `which finger`
    #!/bin/ksh
    /usr/pkg/bin/finger-real -m $*

As a sidequest, $* should probably be written as "$@" to avoid the at best surprising or at worst security-vulnerability introducing shell word-splitting rules. One might also write "exec /usr/pkg/..." as the last line of the script to replace the ksh script with the program being run, but that's less important.

Replacing a command with some other command may also be bad, as that may change the interface, and break scripts that assume "finger" behaves like finger(1). Some folks tried to replace rm(1) with a script that moved files to ~/.trash instead of deleting them, which mostly worked, except when it did not. A better option might be to teach your users to run "trash ..." which does the ~/.trash thing instead of breaking the interface to a commonly used system tool. The risks here depend on how dangerous the tool is. finger, not very; rm, very much so.

The "not logged in" thing (if true) could be due to wtmp issues, maybe the means by which they logged in (via mosh, or maybe by logging in as a "menu" user then being exec'd over to a shell for their account?) did not update the wtmp database. Not everything uses utmp(5), or if there's custom wrapper programs involved who knows what is going on.

Naturally one will want to skim through the relevant manuals, for instance to see what the "-m" flag for (the real) finger does.

    $ man finger
    ...
    $ man 5 utmp
    ...