OPEN and READ a Data File in Perl

You need to get data from the file "cities.txt"

Example Data File (cities.txt):

London
Paris
Tokyo


open(DA, "<cities.txt");
@huhu=<DA>;
close(DA);

print $huhu[2];

Which Prints:

Tokyo


-The left arrow before cities.txt means READ file. (full or relative path if in different directory)
-The contents of cities.txt is now stored in the array @huhu
-The words DA are called a Filehandle. Always use ALL CAPS for filehandles. The DA could be pretty much anything you like except STDIN and STDOUT, which are reserved for other things.


NOTE on How Data is Read:

By default, the data is pieced out (split) by line returns. But line returns can vary by platform or text editor configuration.

So if you are having problems with this example, you can try to SPLIT the array @huhu into chunks of data using:

\r Mac, although this won't always be the case.
\n Unix
\r\n Windows


Start Copy and Paste Perl Code (you'll need to create a file named cities.txt in the same directory as script):

#!/usr/bin/perl

print "Content-type:text/html\n\n";

open(DA, "<cities.txt");
@huhu=<DA>;
close(DA);

print $huhu[2];

exit;

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