While loop to produce file of invalid user names

[MarkSyder]

Hi everybody.

Please see the following section of shell script:

/usr/sbin/acct/fwtmp < /var/adm/btmp > /tmp/bad_logins
while read line
do
awk '{print $1}' >> /tmp/bad_login_names
done < /tmp/bad_logins

The first part is creating the file /tmp/bad_logins without any problem but the second part does not put anything into /tmp/bad_login_names.

Any ideas what could be wrong?

Mark Syder (like the drink but spelt different)

[Kent Ostby · Accepted solution]

Not sure , but would this work instead:

awk '{print $1}' < /tmp/bad_logins >> /tmp/bad_login_names

[Victor Fridyev]

Hi Mark.

The script should look like that:
usr/sbin/acct/fwtmp < /var/adm/btmp > /tmp/bad_logins
awk '{print $1}' /tmp/bad_logins >> /tmp/bad_login_names
or
usr/sbin/acct/fwtmp < /var/adm/btmp |
awk '{print $1}'>> /tmp/bad_login_names


HTH

[Peter Godron]

Mark,
your awk step has no input to process !!
put an
echo $line |
in front of the awk and it should work.
Or use the other solutions given or use cut.
Regards

[MarkSyder]

The first two suggestions both worked (I'd assigned points before I saw Peter's suggestion, but always give 3 for people's time even if I don't use their suggestion).

Thanks for the help.

Mark