Perl match to cut off after second occurrence

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

$SC = "example.pl";
if ($0 =~ m/(.*)$SC/i){ $dir = $1; print $dir."\n";}
[download]

$0 outputs the current directory with the filename being ran, which I'd like to match and remove down to the root directory for any includes that are needed.

Lets say $0 = C:\main1\example.pl using the line above it would change to C:\main1\ cutting off the filename which is good.

Now say the same script was ran from C:\main1\sub1\example.pl my $dir output would be C:\main1\sub1\ but I need that to also be C:\main1\ (the first dir in the output)

So my question is can I match or replace the string in a way that no matter how deep its run the output it cuts off anything past the second \ to keep it no deeper than C:\main1\ ?

Basicly any files that need to be written or read will be in the first dir (C:\main1\) and all subdirs need to be able to point there without using chdir specificly to it or inputting a static directory name. Also the lowest dir will not always have a number so it can't match on numeric followed by a slash or anything to that effect.

Please let me know if this is unclear, thanks in advance for any help.

Comment on Perl match to cut off after second occurrence Download Code

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Re: Perl match to cut off after second occurrence by thenaz (Beadle) on Aug 09, 2011 at 20:51 UTC
Try this: `(my $dir = $0) =~ s/([^\\]+\$[^\\]+\$?)?.*$SC/$1/;`	[reply] [d/l]
Re: Perl match to cut off after second occurrence by happy.barney (Friar) on Aug 10, 2011 at 09:00 UTC
`my $STOP_AFTER_MATCH = 2; (undef, undef, my $dir) = split /\\/, $0, $STOP_AFTER_MATCH + 1;` [download]	[reply] [d/l]
Re: Perl match to cut off after second occurrence by shadowfox (Beadle) on Aug 10, 2011 at 12:56 UTC
I like thenaz's suggestion, it works, a good one liner. I didn't test yours happy.barney but thanks for offering another option. I came up with a very crude alternative last night but its clear I was barking up the wrong tree because it took a lot more code. I could easily do the first or last occourance but those in between was really throwing me how to do with proper syntax. Thanks again to you both,	[reply]

Replies are listed 'Best First'.
Re: Perl match to cut off after second occurrence by thenaz (Beadle) on Aug 09, 2011 at 20:51 UTC
Try this: `(my $dir = $0) =~ s/([^\\]+\\([^\\]+\\)?)?.*$SC/$1/;`	[reply] [d/l]
Re: Perl match to cut off after second occurrence by happy.barney (Friar) on Aug 10, 2011 at 09:00 UTC
`my $STOP_AFTER_MATCH = 2; (undef, undef, my $dir) = split /\\/, $0, $STOP_AFTER_MATCH + 1;` [download]	[reply] [d/l]
Re: Perl match to cut off after second occurrence by shadowfox (Beadle) on Aug 10, 2011 at 12:56 UTC
I like thenaz's suggestion, it works, a good one liner. I didn't test yours happy.barney but thanks for offering another option. I came up with a very crude alternative last night but its clear I was barking up the wrong tree because it took a lot more code. I could easily do the first or last occourance but those in between was really throwing me how to do with proper syntax. Thanks again to you both,	[reply]