Unix administration - Re: Need script to extract from /etc/security/lastlog -> list of users and their la

Author

Re: Need script to extract from /etc/security/lastlog -> list of users and their la

Stephane CHAZELAS

2004-12-17, 7:50 am

2004-12-17, 11:31(+00), Bela Gazdy:
[...]
> Correct. Recycling wtmp, most of the times, means: cat /dev/null > /var/adm/wtmp
[...]

I've always wondered why people would use "cat /dev/null" as a
command that outputs nothing while there are that many other
ones that are built in the shell.

Is it because early Bourne shells had problems when redirecting
builtins?

: > /var/adm/wtmp # the most obvious
eval > /var/adm/wtmp
exec 3> /var/adm/wtmp 3>&-
shift 0 > /var/adm/wtmp
....

(and cd, read, command, printf, builtin, getopts, true, false...).

--
Stephane