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Top Forums Shell Programming and Scripting Improve script - slow process with big files Post 302990412 by rbatte1 on Thursday 26th of January 2017 06:34:58 AM
Old 01-26-2017
The csh shell has many known issues and I would strongly recommending that you don't use it.

I've not read the whole thing, but assuming that you are working through the file, line by line and this design is actually reading the whole file each and every time round your loop, calling 10 processes to split up your line, how about this construct instead:-
Code:
while read tap rec lin pnt spx spy spz tim lfr lto unused
do
   whatever_you_need_here
done < info_records.list

Okay, so this is sh / ksh / bash, but it is far neater and has far lower overheads. I've not got a true csh available and the manual page I have uses all sorts of bash phrasing so it is only imitating some csh scripting so I can't really test anything I write in csh.

You might be better with this csh mangle instead of calling awk all over the place:-
Code:
foreach line ( "`cat input_file`" )
   set parsed = ($line)
   set tap = $parsed[1]
   set rec = $parsed[2]
   set lin = $parsed[3]
   :
   :
end

This reads the file once, and for each line it splits up the record to the variables you want without calling external commands (except the cat that I can't find a way to remove)

Overall though, it is worth the effort to convert to sh based scripts. I hope your code is not riddled with goto statements like I have had to decipher before. That poor programming can leave serious headaches in re-designing.


I hope that this helps,
Robin
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