Update: luckily this whole thread was renamed to "Parsing 'ps' output" from "hull bts"

Hi vineet2004,

given the fast pace you're posting here, it seems that you find this site quite useful, and this is good. I hope you'll understand that much of its usefulness is not only in the general quickness in the answer one can get, or in their quality; one big aspect of this site is that all the questions, answers, thoughts, etc. are kept for future memory. In this way, it is useful today (to whoever asks a question) and it will be useful tomorrow for those who look for something similar (e.g. using Super Search).

One of the key aspects when searching inside the node base is the fact that one can perform a query based on the title of the post. Let's say that I'm looking for something about "regexp matching" - that's exactly what I would type, as a start, inside Super Search within the title entry. Making queries by title is usually faster (titles are short) and this makes title an invaluable resource for nodes categorisation.

Which brings us to your node. Unfortunately, whatever usefulness your post (and the answers I hope you'll receive) could have, they will be missed by those looking for it in the quick way I was talking about. While "hull bts" makes perfectly sense to you, it means probably near to nothing to most people here, which is bad for two reasons: the first is that the community will miss something and the second, more important from your point of view, is that you will get less answers (because you're not actually declaring what you're looking for).

To cope with this, I'd suggest you to read How do I compose an effective node title? and try to apply the suggestions in this node's title and in the future nodes you'll produce for the community. By the way, you could also enjoy How do I post a question effectively?, which will surely give you hints on how to receive (more) lots of answers to your questions.

use strict;

my $correctanswer = "11408";

my $regexp = qr/^([\d]+)*(hullBts_static)/;

while (<DATA>) {
    if ( /$regexp/ ) {
        if ( $1 eq $correctanswer ) {
            print( "Congratulations, the regexp is correct!" );
            exit( 1 );
        } else {
            die( "Error, match was $1" )
        }
    }
}
die( "Error, never matched" );

__DATA__
11299 pts/4    00:00:00 su
11303 pts/4    00:00:00 bash
11403 tty2     00:00:00 bsc_static
11406 tty2     00:00:00 rtpTrau_static
11408 tty2     00:11:30 hullBts_static
11418 pts/4    00:00:00 tail
12157 pts/5    00:00:00 su
[download]

Well if I run this test code I get:

Error, never matched at /tmp/hullbts.pl line 17, <DATA> line 7.
[download]

Clearly something is wrong. I suggest taking a closer look at the regexp and what you're trying to match.

First you want the beginning of a line. Then as many digits in a row as possible. Then anything until we find "hullBts_static". With this in mind let's have another look at a regexp:

my $regexp = qr/
                ^              # beginning of line
                (\d+)          # as many digits as we can find
                .*             # anything at all
                hullBts_static # literally, "hullBts_static"
               /x;
[download]

When substituting this new regexp we get the following output from the test script:

Congratulations, the regexp is correct!
[download]

Note that the /x at the end of the regular expression merely allows us to spread the expression over several lines. That regular expression looks, more compactly, like /^(\d+).*hullBts_static/.

if(/^([\d]+)*(hullBts_static)/)
[download]

if(/^([\d]+).*(hullBts_static)/)
[download]