Path: utzoo!attcan!uunet!olivea!bu.edu!dartvax!eleazar.dartmouth.edu!mjm
From: mjm@eleazar.dartmouth.edu (Andy Behrens)
Newsgroups: comp.unix.shell
Subject: Re: awk question
Message-ID: <1991Feb28.181115.27279@dartvax.dartmouth.edu>
Date: 28 Feb 91 18:11:15 GMT
References: <62322@eerie.acsu.Buffalo.EDU>
Sender: news@dartvax.dartmouth.edu (The News Manager)
Reply-To: andyb@coat.com (Andy Behrens)
Organization: Burlington Coat Factory
Lines: 34

haozhou@acsu.buffalo.edu (Hao Zhou) writes:
> I am using awk to print some selected lines from a text file. What I
> want to to is to hold off the current line until next line comes in
> and a certain condition is satisfied before printing both lines. 
>
>	awk '{{if (condition) \
>		printf("%s \n %s \n", $prev, $0)} 
>	      {prev=$0}}'
>
>However the variable prev doesn't store the previous line. Instead the
>printf prints out twice the current line. What am I doing wrong?

You should write 'prev' instead of '$prev'.  Awk variables (unlike
shell variables) are written without a dollar sign.

The awk statements

	n="3"
	print $n	# or print $(n)

will print the third field of the input line.

--
If you've got a hammer,			       If the only tool you have
find a nail.				    is a hammer, you tend to see
(George Bush, January 29, 1991)			every problem as a nail.
							(Abraham Maslow)
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