From: Daniel Barker <sokal AT holyrood DOT ed DOT ac DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Penalty for immature language (PERL/BASH)
Date: Thu, 1 Mar 2001 20:29:35 +0000
Organization: Edinburgh University
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On Thu, 1 Mar 2001, Eli Zaretskii wrote:

> > At the BASH prompt, I launch the following PERL script, prog.pl:
> > 
> > while(<>)
> > {
> > `$_`
> > }
> > 
> > If I give this a single line consisting of the word "poo", BASH performs
> > an illegal instruction.
> 
> Could you please describe, for the Perl-illiterate such as myself,
> what does this loop do, in the terms of its interaction with the OS?

In pseudocode, something like this:

WHILE (there is an unprocessed line of standard input)
{
	execute that line as if typed at the shell prompt, but
	without printing its output;
} 

`<command_string>` in PERL is very similar to `<command_string>` in BASH.

-- 
Daniel Barker.