Hi, All, :)
I'm trying to write a short script to remove duplicate entries in my
PATH variable. I use Cygwin (Windows NT) and so I use perl from a
bash prompt. Win32 programs *constantly* diddle with the PATH during
installation and I'm sick of having to manually fix it up.
So, I want to write a script (in Perl, of course!) so that I can use
it in my .bash_profile like so:
export $PATH=`perl fixpath.pl`
So, the perl script would read the PATH, chop out any duplicate
entries, and write the new path to stdout.
First off, is this the right way to go about this? I know this isn't
a shell list, but I'm assuming that the perl script can't actually
*change* the PATH in the parent process - only for its own process.
Right?
Assuming this is the way I want to go, here's what I've cooked up so
far:
#!/usr/bin/perl
use strict;
use warnings;
# Strip redundant entries from the PATH environment variable. Print
# out the fixed path.
# The original path.
my @path = split /:/, $ENV{"PATH"};
# Holds the fixed path.
my @newpath;
# Hash used to ignore duplicate entries.
my %entries;
# Loop through each entry in the path sequentially.
while( my $entry = shift @path ) {
# Is this the first occurrence of this entry in the PATH?
if( ! $entries{$entry} ) {
# Yes. Add this to our fixed PATH and store it in our entries
# hash.
push @newpath, $entries{$entry} = $entry;
}
}
# Print out the new path array joined by colons to be a *nix PATH.
print join ":", @newpath;
# End of fixpath.pl.
This works, but it feels really clunky. In my exploration of perl
RE's, I can "sense" that there might be a RE solution to this problem
without having to go to the hassle of creating a bunch of arrays, a
hash, and then looping through the entries.
However, I'm at a loss to see the structure of such an 's///g'
construct. Anybody have any ideas on how I should go about tackling
this?
Thanks in advance for any help!
---Jason Tiller
[EMAIL PROTECTED]
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