topic Re: Can you pass vatiables to awk? in Operating System - HP-UX

Can you pass vatiables to awk?

Jamie Collins — Wed, 13 Oct 2004 16:26:43 GMT

In a shell script:

server=jamie

awk '{if ($2 = $server).....

Re: Can you pass vatiables to awk?

Sridhar Bhaskarla — Wed, 13 Oct 2004 16:30:13 GMT

Hi Jamie,

Yes. You will have use -v flag with awk to pass them. For ex.,

string="Sridhar"
echo "test" |awk -v name=$string '{print name}'

-Sri

Re: Can you pass vatiables to awk?

Jamie Collins — Wed, 13 Oct 2004 16:33:27 GMT

I got it to work with the following as well:

awk '{if ($2 = "'$server'"...

Thanks

Re: Can you pass vatiables to awk?

Sridhar Bhaskarla — Wed, 13 Oct 2004 16:40:04 GMT

Yeah.. its' the same way

server=jamie

awk -v server=$server '{if ($2 = $server)...

-Sri

Re: Can you pass vatiables to awk?

Jamie Collins — Wed, 13 Oct 2004 16:47:57 GMT

Actually it dosn't work either way...

Instead of the string 'jamie' I get:

if $2 = server

I tried it with $server and "$server" but it doesn't work...

Re: Can you pass vatiables to awk?

A. Clay Stephenson — Wed, 13 Oct 2004 16:50:13 GMT

That's because in awk only positional variables ($1,$2, ...) get the $; all user defined variables do not use the $ prefix.

Re: Can you pass vatiables to awk?

Sridhar Bhaskarla — Wed, 13 Oct 2004 16:56:41 GMT

I simply cut and pasted your line. I didn't realize you had a $ in front of $server. Look at my first example where I didn't use $ in front of 'name'.

-Sri

Re: Can you pass vatiables to awk?

Muthukumar_5 — Wed, 13 Oct 2004 16:57:58 GMT

Yes. We can do this as,

echo "jamie" | awk '{ if ( $1 == server ) print "ok" }' server=jamie

It will pass that environment variable of server with jamie string there.

You can more check as,

echo "hai" | awk '{ print server }' server=jamie

HTH.

Re: Can you pass vatiables to awk?

Jamie Collins — Wed, 13 Oct 2004 17:01:50 GMT

Here's what I get... (changed the variables to do a time range instead...)

server_time="07:08:55"
awk -v time=$server_time {if ($9 < time && $10 > time)

when I debug it looks like this:

awk -v time=07:08:55 {if ($9 < time && $10 > time)

shouldn't the time be replaced with the value of the time variable?

Re: Can you pass vatiables to awk?

Muthukumar_5 — Wed, 13 Oct 2004 17:08:13 GMT

You can also --assign var=value on awk too.

It is as,

echo "hai jamie" | awk --assign server=jamie '{ if ( $1 == server ) print "OK" }'

Else try awk -v =value

see man awk.

HTH.

Re: Can you pass vatiables to awk?

Sridhar Bhaskarla — Wed, 13 Oct 2004 17:23:56 GMT

Hi Jamie,

Your time variable should get passed correctly but your 'test' conditions may produce unexpected results as the time variable is treated as 'text' and using <,> operators on it may not give what you expect.

-Sri

Re: Can you pass vatiables to awk?

Sridhar Bhaskarla — Wed, 13 Oct 2004 17:26:39 GMT

...and just to confirm that your time variable is passed correctly, put a "print time" statement in your awk script.

-Sri

Re: Can you pass vatiables to awk?

Jamie Collins — Wed, 13 Oct 2004 17:31:45 GMT

I see now that the variable is getting passed corectly.. my error is now in my script. I'm going to keep playing...
Thanks

Re: Can you pass vatiables to awk?

Muthukumar_5 — Wed, 13 Oct 2004 17:34:49 GMT

Hai Jamie,

Started to play with awk right now. If you get your problem solved, treat responders with points to get more informations in near future and get good interaction.

Best wishes.
Muthukumar.