When my tomcat context suddenly wouldn’t start anymore I found myself scratching my head. I couldn’t figure out why the startup.sh script always threw the error

bash: ./catalina.sh: /bin/sh^M: bad interpreter: No such file or directory

After investigating for a while I found that I had two seemingly identical files. One would run fine, the other threw a “bad interpreter” error.

Apparently if a shell script gets opened and saved in notepad it will not run anymore.

A simple “dos2unix catalina.sh” fixed the problem.

In Ubuntu the dos2unix binary can be found in the tofrodos package.

I was amazed to see how simple Perl makes it to read the lines of a file into an array.

#!/usr/bin/perl
open(I, “flavors.txt”);
@flavors = <I>;

With just two lines of code, you are ready to do some string munching. You can then run through the elements in the array with a loop similar to the following.

for($i=0; $i<@flavors.length; $i++) {
@flavors[i] =~ s/•//;
}

I would enjoy seeing some other ways to iterate through the array.

Here is an example of brute force engine searching. It does nothing more than perform a large number of searches in a very short time. Beware this is not a very nice thing to do and it is a terrible waste of network, and CPU resources. This is given as an example of the power of cURL. This script is written in PHP and uses the libcurl libraries.
[code lang="php"]
$base_url = "http://www.google.com/search";
$ch = curl_init();

for($i=0; $i<20; $i++) {
$url = $base_url . "?q=$i";
curl_setopt($ch, CURLOPT_URL, $url);
curl_exec($ch);
}

curl_close($ch);
?>
[/code]