Mark Hensler — Tue, 04 Sep 2001 15:42:05 +0000

Welcome to TWF, Jm4n!

Very usefull information, thanks!

merlin — Tue, 04 Sep 2001 10:41:03 +0000

well, i didn't know all that stuff. thank you for the information (not as useless as you're saying... )

Jm4n — Tue, 04 Sep 2001 10:18:58 +0000

Well, apparently you figured it out, but to explain what I know about it:

Any shell script on a Unix system starts with a 'bang line', or 'shebang line'. This line is always a # sign, an ! mark, and the path to the interpretor.

#!/usr/bin/perl

The reason it starts with a # sign is that you can run this script through the interpretor directly -- in which case that line is simply ignored.

Perl never sees that line when a Perl script is executed directly. The operating system sees it, and decides it's a text-based script. It then finds the interpretor, and executes it, giving the script filename as an argument:

/usr/bin/perl scriptname.pl

The short answer is that Perl (or sh or other shell scripting language) will ignore the line, as it should. Only the system (or the web server) needs to interpret the line.

---
Little known facts:

- Most people don't know this, but it does not have to be the first line. You can have blank lines and comments before it, just no code.

- In most cases with Perl scripts, if you put a single hyphen as the last argument, you can forget about having to upload in ASCII mode:

#!/usr/bin/perl --

See, it's not Perl that cares about line terminations, Perl is cross-platform. It's the operating system that causes the problem; It sees the CR (carriage return) as being part of the command line, which when passed to perl is an invalid argument.

The last hyphen tells Perl to ignore the rest of the command line (over-simplified explanation); thus, when it sees the CR that Windows or MAC uses to terminate lines, it will simply ignore it instead of giving an error. If all scripts shipped like this, the most common script problem would simply go away

But enough useless information...

tmay — Mon, 03 Sep 2001 20:17:27 +0000

Nevermind