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August 2013

Printing multiple files   by Anthony Lawrence
- I have 25 .txt files that I would like to print. They are named 1.txt, 2.txt and so on. How can I do this?
Sparse Files   by Anthony Lawrence
- Sparse files are a result of the way systems allocate storage space. Sparse files appear to take up much more disk space than they actually do.
Length of a domain name   by Anthony Lawrence
- What IS the longest possible domain name and why isn't it in the book of Guinness World Records? While we're at it, what is a domain name anyway?
Run a script every other day but not on weekends   by Anthony Lawrence
- While this became much easier with Vixie cron, there are still circumstances that need some extra help in the script.
Is rm final? Can I get my files back?   by Anthony Lawrence
- Is rm final? Are the files gone forever? It depends on what you mean by really gone and also depends upon your file system, your OS, and rm itself.
How do I compress my backups? 
- Well, you could just run the output of tar, cpio, or whatever through compress but if even one bit of your tape or diskette goes bad, you could lose the rest of the backup.
A note for long time readers   by Anthony Lawrence
- At one point I was ready to give up. I'm nearing retirement and, while the extra income this site used to produce was nice, at its current state I'd be better off bagging groceries than spending time on this.
All about ping   by Anthony Lawrence
- Ping is a useful network diagnostic, but it can have its own issues - timeouts, duplicate packets, intermittent issues
Value of bit-level verifying a backup 
- You'd probably be surprised how often a bit level verify proves useful. I receive backup status email for several of my clients, so I can tell you that bit-level verification "failures" are not all that uncommon.
Perl directory listing 
- A "pretty" or custom directory listing is a good place to start developing your scripting skills if you want to. There certainly are utilities that do pretty listings, but the advantage of rolling your own is that you can do EXACTLY what you want and gain some useful skills while you are at it.
Removing empty directories   by Anthony Lawrence
- Follow along as we segue and digress, dive deep and reverse ourselves all while trying to avoid the pedantic spoilers who would surely ruin our fun emptying our directories.
Why use private network addresses 
- I still see systems where people have used public ip addresses for private networks. These sometimes even end up behind a NAT firewall and while they "work", problems are out there.
Basic software firewall introduction for home users  
- You almost certainly have a software firewall on your Windows or Mac computer. You also probably have a hardware firewall. Understanding just a little bit about them can save you trouble.
tput and stty   by Anthony Lawrence
- tput and stty are related in the sense that they both have to do with how a Unix terminal behaves. Tput is perhaps less important than it used to be, but still useful
'ps' and 'grep'   by Anthony Lawrence
- Grepping lines out of ps is a common task. Unfortunately, it's also easy to go terribly wrong and not get what you expected at all.
Are pdf files dumb? 
- PDF is great if you really need it, but I see far too much PDF used where HTML would have been a better choice because there was no need to control the display.
Trapping errors in Bash   by Anthony Lawrence
- While I think you need to avoid getting too clever in shell scripts, trapping errors can be useful.
System Administrator wanted   by Anthony Lawrence
- System Administrator wanted. Skills needed go far beyond what is listed here, but none of these can be lacking
Expectations of privacy - time to shut it down?   by Anthony Lawrence
- Groklaw shuts down, the NSA spying gets worse. Is this Orwellian or just business as usual?
Let's be serious about System Administration   by Anthony Lawrence
- Like Rodney Dangerfield, SysAdmins don't always get the respect they deserve.
The Seven Layer inedible OSI cake   by Anthony Lawrence
- The other day I had to explain the OSI model to a customer. I'm not usually this cruel, but (as they say) he asked for it.
The king is dead, long live Microsoft   by Anthony Lawrence
- There are other struggling companies where Ballmer's magic touch might bring back the gold. Of course Apple and Google spring immediately to mind.
The truth about Linux   by Anthony Lawrence
- I have been lying to you. You should NEVER use Linux for anything! Pay attention as I explain.
I want YOU at Bubblews   by Anthony Lawrence
- This may be a waste of your time. It may not. It could disappear tomorrow or it could be important.
Trying out Cloudflare   by Anthony Lawrence
- I'm trying out Cloudflare. I'm a little nervous, but it looks good so far. We will see, won't we?
More about Cloudflare   by Anthony Lawrence
- CloudFlare should now be fully active on this site. Visitors should only see speedups in page loads and no adverse affects.