How to do this in Perl ??

wube has asked for the wisdom of the Perl Monks concerning the following question:

Hello enlightened brothers and sisters. I am a newbie to UNIX and to Perl. I have written a script to fix a problem we had a couple of days ago and I was wondering if the same could be done in Perl. The Bourne script follows:

#!/bin/sh
#
# This script fixes the ownership of all files that is in /var/sadm/in
+stall
#  It bypasses 3 directories /usr
#                            /usr/lib
#                            /usr/openwin
#
WKDIR=/var/sadm/install  
cd  $WKDIR
#
egrep -v "/usr d |/usr/lib d |/usr/openwin d " contents | grep ' d ' |
+ awk '{ print "chown -R " $5":"$6,$1 }' > /tmp/fixchown.sh
[download]

Any assistance towards reaching Nirvana will be greatly appreciated.
wube

Edit kudra, 2001-11-14 Added code tags

Comment on How to do this in Perl ?? Download Code

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Re: How to do this in Perl ?? by VSarkiss (Monsignor) on Nov 13, 2001 at 21:19 UTC
"Can it be done in Perl"? Do we need to discuss Turing-completeness? I think what you mean to ask is "How easily can this be done in Perl?" to which the answer is, "Very easily." `#! /usr/bin/perl -w use strict; my $wkdir = '/var/sadm/install'; chdir $wkdir or die "Couldn't cd to $wkdir: $!\n"; open I, 'contents' or die "Couldn't open 'contents': $!\n"; my @line; while (<I>) { next if m{/usr d\|/usr/lib d\|/usr/openwin d}; if (/ d /) { @line = split; system("chown -R $line[4]:$line[5] $line[0]"); } } close I; # be polite` [download] (Note, I haven't tested this.) As always, TIMTOWTDI. (This may even touch off a round of golf. ;-) Notice I didn't write the `chown` commands to a script, I just executed them directly. There are other optimizations possible, but I just wanted to make the correspondence to your script very clear. HTH Update Changed `cd` to `chdir`. Thanks, blakem!	[reply] [d/l] [select]
Re: Re: How to do this in Perl ?? by belg4mit (Prior) on Nov 13, 2001 at 21:47 UTC
You can take a few strokes off by inserting `use File::Find;` after line 2 and replacing `system(...)` with `find(sub { chown($line[4], $line[5], $File::Find::name); }, $line[0]);` [download] pop; pop(@FIZZ); @FIZZ;	[reply] [d/l]
Re: Re: How to do this in Perl ?? by blakem (Monsignor) on Nov 14, 2001 at 01:13 UTC
One minor point: cd is spelled chdir in perl... -Blake	[reply]
Re: Re: How to do this in Perl ?? by wube (Acolyte) on Nov 15, 2001 at 18:58 UTC
I will play with this. Thanks to all that replied wube	[reply]
Re: How to do this in Perl ?? by brianarn (Chaplain) on Nov 13, 2001 at 21:08 UTC
I'm sure it can be, except your code isn't exactly easy to break down right now because it's all running together - try putting <CODE></CODE> tags around your script - then someone'll be able to read it and break it down much easier :) ~Brian	[reply]