topic Re: awk script help in Operating System - HP-UX

Script Help

allanm77 — Sat, 10 Aug 2013 19:03:55 GMT

I have this following script which lists out packages on a filesystem (but NOT the latest package) on a filesystem.

I want to avoid listing out the latest 3 packages instead of one.

ls -l | awk '
BEGIN { prev = ""; app = "" }
{
n = split($9, apps, "-")
if (n == 0) next
if (n < 2) {
   print "problem getting appname for", $9
   next
}
appname = apps[1]
if (appname == app) {
   print prev # older
   prev = $9   # save
   next
}
app = appname
prev = $9
} '

Thanks,

Allan.

Re: awk script help

Dennis Handly — Tue, 13 Aug 2013 07:19:06 GMT

>I want to avoid listing out the latest 3 packages instead of one.

I suppose you could have multiple "prev" buffers and shuffle them down.

Or create a circular buffer.

BEGIN { app = "" }

...

if (appname == app) {

if (prev[nn] != "")

print prev[nn] # older

prev[nn++] = $9 # save

if (nn >=3) nn = 0
next
}
app = appname

# flush prev array

for (nn in prev) delete prev[nn]

nn = 0
prev[nn++] = $9 # save
} '

Re: awk script help

allanm77 — Sun, 11 Aug 2013 16:15:03 GMT

Thanks Dennis, for the reply.

I tried the circular buffer but that shows the latest packge.

Allan.

Re: awk script help

Dennis Handly — Mon, 12 Aug 2013 19:47:24 GMT

>I tried the circular buffer but that shows the latest package.

Hmm, I'll have to check it out later to day.

Have you tried only 1, 2, 3, 4, 5, 6 packages and see what happens?

Re: awk script help

Dennis Handly — Tue, 13 Aug 2013 07:21:24 GMT

>I tried the circular buffer but that shows the latest package.

Rats! A conflict in your variable "n" and mine. I've updated it to use "nn".

It seems to work fine.

BTW. If you pipe the result of your awk script 3 times, you can do the same thing. ;-)