Date:         Wed, 6 Mar 2002 09:18:42 -0800
Reply-To:     "Schwarz, Barry A" <barry.a.schwarz@BOEING.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         "Schwarz, Barry A" <barry.a.schwarz@BOEING.COM>
Subject:      Re: How to read previous lines based upon string in current line.
Content-Type: text/plain

Create two retained variables (PREV1 and PREV2) suitable for holding a line
each.  Just before you iterate the loop, set PREV1 to PREV2 and set PREV2 to
the current line.  In each iteration, the two previous lines will always be
available if you decide you need them.


Barry Schwarz
OS/390 Systems Programmer
Phone:      253-773-4221
Fax:        253-773-1257
Mail stop:  80-JE
e-mail:     barry.a.schwarz@boeing.com




> ----------
> From:         Carriere, Ron[SMTP:rcarriere@MEDNET.UCLA.EDU]
> Reply To:     Carriere, Ron
> Sent:         Tuesday, March 05, 2002 11:23 AM
> To:   SAS-L@LISTSERV.UGA.EDU
> Subject:      How to read previous lines based upon string in current
> line.
>
> I have dataset that consists of 40K+ lines of MVS JCL.  I am attempting to
> output a list of datasets cataloged by that JCL.  Pseudo code for the task
> would be
>
>     Read a line;
>
>      IF a line contains the string "CATLG" then do;
>          if  line contains "dsn=' then
>               output the line;
>           else  do;
>              read and then output the two previous and then the
>              current line;
>           end;
>      end;
>
> The "else do" part is required because the dataset name is sometimes on
> one of the two previous lines.  That is part I can't accomplish without
> sorting and resorting the dataset, but there must be a better way using
> line pointer controls, no?
>
> Ron Carriere
> UCLA Medical Center
>