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Mac Screen sharing is not just for Macs Mac's new Leopard OS X has added a "Screen Sharing" capability. For Mac A to control Mac B's screen, Mac B simply has to turn on Screen Sharing in System Preferences->Sharing. Mac B will show up in Mac A's sidebar in Finder Windows, and clicking on that will offer a "Share Screen" button that let's you connect.

Title Date Comments
Unix and Linux startup scripts, Part 1   2009 12 
- In the beginning, there was "init". If you had a Unix system, you had "init" and it was almost certainly process id 1. -
Unix and Linux startup scripts, Part 2   2009 12  2009/12/11 TonyLawrence
- The rc.d system is used on NetBSD, FreeBSD and DragonFly (andpossibly a few other systems) to launch daemon processes when the system goes multiuser. -
Unix and Linux startup scripts, Part 3   2009 12 
- We have looked at both System V and BSD methods; until fairly recently that would hav e been the end of the discussion. -
Creating pretty graphs with RRDTOOL   2009 08  2014/09/03 Varun
- The open source rrdtool project helps you create a graphical view of any statistic collected at regular intervals. -
VMware Networks, Bridged vs. Nat vs. Host   2008 12  2011/05/19 Firedancerx
- Understanding VMware networking options. By default, VMware works in "bridged" mode - you use the card by attaching a virtual network device to it. -
Mac OS X Dual Monitors   2008 02  2012/09/21 TonyLawrence
- Dual monitors aren't well done on OS X but can still be very useful. So how do you set up dual monitors on your Mac? Pretty simple: plug it in. -
Symbols and Apes   2008 02 
- We are masters of abstraction and indirection. Programmers know that perhaps even more than other people; our world is almost all symbols. But all of us, programmers or not, use symbols every day of our lives. We also often use ritual, and rituals often involve symbols - Wikipedia even defines ritual as "a set of actions, performed mainly for their symbolic value..". -
Mac Screen sharing is not just for Macs   2008 01  2015/03/21 TonyLawrence
- Mac Screen Sharing can connect to any VNC host. That's Mac Screen Sharing connecting to a TightVNC server on my wife's Windows XP machine. -
Google Earth Street View   2007 06  2011/10/14 bchopper
- I'm sorry. The ACLU will probably want their card back, but I just don't see cameras as a privacy problem. -
Cron is not working   2006 12  2012/08/17 TonyLawrence
- Let's just get this out of the way first: when someone says cron is not working, it almost always is, and they have just misunderstood something basic. -
Finding large files   2006 12  2010/10/02 wilson
- Where has the space gone? Although it is getting harder and harder to run out of disk space, some of us still manage to do it. -
Using Bluetooth phones with Mac OS X   2006 11  2013/09/13 TonyLawrence
- Transfer pictures from bluetooth phones, difficulties and solutions. Like so many Mac operations, getting pictures from a Bluetooth phone to your Mac is actually very simple once you have done it once. If you've never done it, you may not have a clue where to start, and your phone's manual probably sends you off to get some piece of Windows software that won't help you at all. That's OK: everything you need is already built into your Mac. -
Mac OS X ipconfig   2006 07  2012/02/26 TonyLawrence
- ipconfig on Mac is not like the Windows command of the same name, but is still very useful. If you momentarily forget where you are at a Mac OS X terminal session, you might type "ipconfig /all" or something equally Windowish. You will get a response: -
OS X ACL usage   2006 07  2011/08/11 AndyCanfield
- ACL use in OS X. The "chown" man page tells you about their usage, but it leaves a little bit out and isn't all that helpful. -
Office on Terminal Server   2006 06  2013/03/15 anonymous
- Installing Microsoft Office on terminal server - licensing issues -
OS X file encryption   2006 05 
- File encryption for Mac OS X. I'm going to look at two methods for encrypting files on Mac OS X. The first is built in, and uses DisK Utilty to create an encrypted disk image. -
mount --bind   2006 04  2012/01/03 Daniel
- Using Linux 'mount --bind' instead of symbolic links. If the thing you want to link to is a mounted file system, you can use the "--bind" option of mount to create an unbreakable link. -
Recursive chown   2006 03  2014/02/07 Joe
- 'chown -R' is smarter than you think. I had email this morning from someone using "chown" to fix up permissions on a directory. He had discovered "-R" in the man page but had run into a small problem... That succesfully changed the ownership of the "dot" files, but had an unexpected (to him) side effect: /usr was also changed. -
Enabling Linux telnet   2006 03  2012/09/05 TonyLawrence
- If you can't use ssh (as you should!), you'll need to find and install a telnet daemon for your Linux distro. -
Samepage - Redefining how people create and share information
Backing up Windows machines using rsync and ssh   2005 12 
- Rsync and SSh aren't just for Unix and Linux: Windows and Mac can use these to backup data. -
Bash in-process regular expressions   2005 09  2015/02/21 TonyLawrence
- Bash acquired in-process regular expressions in version 3.0, but I never noticed, probably because most of the machines I'm using are Bash 2.05b. -
Understanding PAM   2005 03  2014/12/09 TonyLawrence
- PAM is the Pluggable Authentication Module, invented by Sun. It's a beautiful concept, but it can be confusing and even intimidating at first. -
Controlling core files (Linux)   2005 03  2011/11/06 TonyLawrence
- Control Linux core files with ulimit and /proc templates. -
Map network drive, connect as different user to same Server   2005 02  2011/11/02 anonymous
- How to map an XP network drive more than once even though XP doesn't want you to do that. -
Writing and Compiling C programs on Linux   2004 12  2012/02/10 TonyLawrence
- Writing and compiling c programs on Linux, common errors for beginners. Most Linux and Unix programs are written in C. When you download source for a project, it will often be C or C++ source code. You don't necessarily need to know a darn thing about C or anything else to compile the source if you aren't changing it. It may be helpful for you to understand a bit if you are having problems with the compile, but even that isn't really necessary. -
Terminal server, Remote Desktop, thin clients and all that   2004 11 
- No wonder people get confused. Lots of similar or related things, no end of licensing confusion, no end of general confusion. Let's try to cut through some of it. First, let's move back and look at the original Unix style multi-user model: dumb terminals, green screens (even if they were orange or white), the character based environment that all Windows folk loathe and disparage. How did that work? The application ran on the Unix server, and only sent characters back to the terminal, and the terminal only sent keystrokes to the Unix box. -
Rebuilding failed Linux software RAID   2004 10  2011/10/26 kuntergunt
- Rebuild crashed Linux raid. Recently I had a hard drive fail. It was part of a Linux software RAID 1 (mirrored drives), so we lost no data, and just needed to replace hardware. However, the raid does requires rebuilding. A hardware array would usually automatically rebuild upon drive replacement, but this needed some help. -
Basic DNS: PTR records and why you care   2004 07  2011/05/02 BigDumbDinosaur
- A PTR record (sometimes called a "host PTR record") is what lets someone do a "reverse" DNS lookup - that is, they have your IP address and want to know what your host/domain is. -
UNIX Basics-JOB SCHEDULING   2004 05  2014/06/19 anonymous
- Basics of Cron scheduling. In the UNIX or Linux environment, it is possible to asynchronously execute tasks at any desired time of the day, a feature made possible by the cron clock daemon. -
The Gimp: Making Colors in a GIF Transparent   2004 01 
- Sometimes when working with an image you want to make a certain color transparent. When working with a gif file this would make a round circle look round on any color background. This is actually very simple once you do it once. Finding the information for this took me a while so I thought I would pass it on to anyone that was interested. -
Lost root password (Linux)   2003 12  2014/12/22 TonyLawrence
- Let's try to fix your lost root password the easy way first. The first thing to try is to boot to single user mode. This MIGHT not work for you, because your system might be configured to still ask for a root password to get to single user mode. If that's the case, we'll use another trick that replaces init with /bin/bash. -
Monitoring file or directory changes   2003 11  2013/02/01 anonymous
- Many modern systems provide a way to watch a directory for events but sometimes brute force or trickery is still needed. -
Perl Input   2003 10  2011/04/08 TonyLawrence
- Perl has wonderful I/O capabilities. I'm only going to cover input here: reading from files or standard input. There are two ways to do that (actually a lot more than two, but this is supposed to be introductory material): you can open a specific file, or you can pass files on the command line and either open them individually or just ignore the whole thing and pretend everything is coming from STDIN. -
Tightvnc, Chicken of the VNC   2003 10 
- Reviews of TightVNC and Chicken of the VNC. VNC is "Virtual Network Computing" and is a crossplatform method of allowing remote access to desktops (Windows or Unix/Linux, Mac and others)). It is conceptually like using Terminal Services or PcAnywhere etc for Windows but is license free and of course capable of serving Linux/Unix machines also. -
Getopt and getopts   2003 09  2013/06/28 TonyLawrence
- Both "getopt" and getopts are tools to use for processing and validating shell script arguments. They are similar, but not identical. -
Perl Getopt and GetOptions   2003 09  2013/02/26 TonyLawrence
- Two Perl modules (Getopt and Getoptions::Long) work to extract program flags and arguments much like Getopt and Getopts do for shell programming. The Perl modules, especially GetOptions::Long, are much more powerful and flexible. -
Perl Net::FTP   2003 09  2013/09/26 TonyLawrence
- Before the wide spread availability of Perl, I would script ftp transfers with .netrc, ksh scripts and other clumsy ways. None of those methods are fun, flexible or easy. On the other hand, Perl's Net::FTP module is all of that. -
Virtual PC for Mac OS X   2003 07 
- This is a review of an ancient Virtual PC product and is only left here for historical purposes. -
Operating System Concepts   2003 05 
- Basic OS concepts. The CPU (Central Processing Unit) is the heart of any computer, but the operating system is the brain. Unfortunately, understanding exactly how these things really work can be difficult, because it's fairly hard to "play" with the operating system that you are actually using. You can do quite a bit with sophisticated debuggers, but eventually you run into confusion and difficulty. And, as you try more complex tasks, you run the risk of interfering with the real machine's operating system. Finally, modern CPU's are very complex, and that complexity can make it more difficult to understand basic concepts. -
Apt-get for RedHat Linux   2003 03  2011/11/08 TonyLawrence
- RedHat 7.3 and 8.0 do not have tools like Mandrakes urpmi for installing/updating rpms. After researching on Google groups for a similiar Redhat tool . APT seemed to be the best. I think its a tool from Debian linux. -
Using the shell (Terminal) in Mac OS X   2002 12  2013/01/27 TonyLawrence
- Many Mac OS X users will not have any need to use the Unix shell that underlies their graphical interface. They are missing out. -
Linux|Unix Logical Volume Manager (LVM) on Software RAID   2002 11  2011/01/07 TonyLawrence
- Logical Volume Manager is now included with most Linux distributions. The RedHat 8.0 installer even allows you to create LVM volumes during initial install. LVM offers capabilities previously only found in expensive products like Veritas. If you plan on using LVM, I really recommend doing so on a RAID system, either hardware or software -
Using sudo   2002 02  2015/02/02 TonyLawrence
- I'm sure that there are more poorly written man pages, but "man sudoers" (which is how you find out about "sudo") is among my all time favorites for poor explanation. Let's clear that up. -
GPG/PGP Basics   2001 11  2014/10/29 anonymous
- Using gpg for encryption, understanding the basic use of GPG for new users. Recently someone asked me for a GPG or PGP public key so that they could send some sensitive material to me by email. -
Automating Program Startup   2000 03 
- automating program startup methods. When you need something to start automatically, there are several ways to do it. Which one you use depends on your specific needs. -
How can I recursively grep through sub-directories?   2003 12  2013/07/18 IrfanRashid
- How to grep through sub-directories whether or not your Unix has recursive (GNU) grep. -
How can I automate an ftp transfer?   2007 06  2011/02/03 Bagbot
- If your script is complex, I'd use use Perl Net::FTP or Kermit. You can also use "here" files fpr simple cases: -
(SCO Unix)How can I send email attachments from the command line?   2003 12  2011/02/01 anonymous
- Sending attachments from the command line with mutt, uuencode and other methods. If it's just arbitrary text or a file you want to send, and don't care about it looking like a real attachment, you can use ordinary "mail" ("mailx" on some Unixes) at the command line. However, that's NOT a mime attachment - it's just your file mixed in to the mail message. However, some mail clients will see it and treat it as a real attachment, so this may be "good enough": -
(SCO Unix)How can I rename multiple files using wildcards?   2003 12  2010/02/10 TonyLawrence
- (SCO Unix) How can I rename multiple files using wildcards if I don't have Linux "rename"? -
(SCO Unix)How do I clear log files?   2003 12 
- (SCO Unix) There is a proper way to clean out log files - don't make the mistake of removing them! -
Kerio Connect Mailserver
(SCO Unix)How do I add a default route?   2003 12 
- How to add a default route on various versions of SCO Unix and have it survive a reboot. -
Kerio Control Firewall

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