February 2012
Intermediate to advanced
1184 pages
37h 17m
English
Content preview from Programming Perl, 4th EditionBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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ops
perl –M–ops=system ... # disable the "system" opcode
The ops pragma disables certain opcodes, with irreversible global effect.
The Perl interpreter always compiles Perl source into an internal
representation of opcodes before it runs it. By default, there are no
restrictions on which opcodes Perl will run. Disabling opcodes restricts
what Perl will compile; any code that would use a disable opcode causes a
compilation error. Don’t think that this provides robust security, though.
The Opcode module has more details about opcodes. Also see the
Safe module (Chapter 20), which might be a
better choice for you.
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.