#798910 coreutils: /usr/bin/who --lookup does not look up ip addresses in dns

Package:
coreutils
Source:
coreutils
Description:
GNU core utilities
Submitter:
Michael Grant
Date:
2025-03-30 22:39:02 UTC
Severity:
normal
#798910#5
Date:
2015-09-14 01:27:28 UTC
From:
To:
Dear Maintainer,

/usr/bin/who used to cannonicalize hostnames by looking the ip address
up in DNS.  Recently this changed and this is no longer the default.
It now always prints the ip address.

It is often desirable to see the hostnames looked up in DNS.

There is a command line option: --lookup
              attempt to canonicalize hostnames via DNS

This option appears to have no effect.  At minimum this should be fixed.

Incidentally and I'm not sure if it's related, the following commands
now only print the IP address instead of the hostname:

/usr/bin/w
/usr/bin/finger
/usr/bin/last

Not sure why this behavior changed but in my opionion it shouldn't
have.  In preference, a command line options should have been provided
to print out the ip address instead of the name (who has --ips) and on
bsd systems, the w command has -n option.
#798910#10
Date:
2024-06-20 16:58:08 UTC
From:
To:
I see the same bug, a bit annoying. 

Fails on IPv6 or IPv4.

Interesting data point is that RH based distros still do the lookup,
and with or without the "--lookup" flag.
#798910#15
Date:
2025-03-30 22:27:08 UTC
From:
To:
This bug is still present in trixie (who (GNU coreutils) 9.5).

Thank you