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Books have been written on the subject of awk and sed. Here’s a small sample of commands I put together over the years that are useful for everyday system administration tasks. Most of these tasks …

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Articles in Cell Phones

Hold Off on iOS 9 iPhone Upgrade

September 21, 2015 – 2:16 pm
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If you haven’t updated your iPhone 6/6 Plus to the recently-released iOS 9, I’d suggest you hold off for a few weeks. Several bugs – including a significant security hole – have surfaced that will …

iPhone Stopped Syncing with Google Calendar

April 3, 2013 – 3:05 pm
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A small but potentially annoying problem: on rare occasions, your iPhone/iPad may decide your calendar looks full enough and will stop syncing with your Google calendar. This is a situation where:

Calendar sync between your iDevice and …

Jailbreaking My iPhone 4S

February 21, 2013 – 11:45 pm
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An iPhone 4S is a fairly sophisticated computer capable of doing many interesting things. Unfortunately, since most phone users are computer idiots, to preserve its bottom line and the sanity of its tech support staff, Apple imposes severe limitations on what you, as a user, can do with your iPhone or iPad. As a Unix sysadmin I am entirely on Apple’s side on this one. However, it would have been nice if Apple allowed an option of full access in exchange for voluntarily voiding the warranty. For those of us who know what they are doing and are not gonna run in tears to the nearest Genius Bar if something goes wrong…

Photo Fun with iPhone 4S

December 19, 2011 – 3:16 am
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As an avid amateur photographer I would like to have my dSLR with me at all times. And my collection of lenses. And filters. And tripods. But even if this was possible, I don’t really want to be, say, sitting at a bar, looking like I just returned from a Serengeti safari. My iPhone will have to suffice and I’ll just have to get more creative with the photos apps to fill in for the fancy equipment.

Disable Usage Information Sharing on iPhone

December 19, 2011 – 1:23 am
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Carrier IQ is software installed on your iPhone by Apple at the request of the service providers. This system utility collect detailed usage and location data on your phone and sends it to the service providers. Supposedly, this was done to improve quality of service. In reality, however, if any such improvement actually occurred, it was only a side-effect.

Photo Noise Reduction Apps for iPhone

December 7, 2011 – 3:59 am
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In digital cameras, image noise (grain) is most pronounced in photos taken in low-light conditions without a flash. For such situations, the camera sets high ISO (light sensitivity of the image sensor) and a long exposure. A number of apps are available for the iPhone to reduce the appearance of grain. None of these apps are particularly impressive, especially when compared to specialized PC software. There is a good reason for this: digital noise reduction is a very CPU-intensive process that also requires a large amount of memory.

iPhone 4S HDR Performance

November 8, 2011 – 5:31 pm
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HDR – High Dynamic Range – photography is a method of achieving a degree of visual detail in highlights and shadows beyond what the camera’s image sensor can record in a single exposure. The HDR processing usually involves combining two or more frames taken at different exposures. This is done on the computer or inside the camera itself. Human vision uses the HDR approach.

Fun with Call Forwarding

October 31, 2011 – 10:20 pm

Sometimes you don’t want people to reach you on your phone, but you don’t want to do something obvious, like turning the phone off. Because then they’ll just leave you a message and you will still be expected to call back. Below is a list of phone number in various US area codes that you can use to forward your unwanted calls.

iPhone 4S: Photo Camera Performance

October 16, 2011 – 9:46 pm
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Here’s our quick-and-dirty test of the new iPhone 4S 8-megapixel camera with LED flash and autofocus. For comparison, we took some of the same photos using a Canon G10 14.7-megapixel compact camera with a 28-140mm wide zoom lens. All photos have been corrected in Photoshop by a professional photographer to produce the best possible result for each camera. iPhone 4S was used in HDR mode.

Enable Foreign Keyboard on iPhone

August 16, 2011 – 1:38 pm
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This is a simple one, but people are always asking: how do I type in Russian, Swedish, Spanish, whatever on my iPhone? Go to Settings -> General -> International -> Keyboards -> Add New Keyboard -> select your language -> select Hardware Keyboard Layout (if applicable).

iPhone OS 4 Upgrade: One Month Later

October 13, 2010 – 1:36 am
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Over a month has passed since I upgraded my iPhone 3Gs to OS 4. There are a couple of significant issues that I noticed. First, the battery life – not particularly impressive to begin with – got shorter. Before I used to get through the day on one charge. I only charged my iPhone overnight. Now, in addition to the nightly charge, I find I need to use the car charger on the way from work to keep the iPhone alive. Since there have been no changes in how I use my iPhone, I have to assume OS 4 causes iPhone to consume more power.

iPhone 3GS OS4 Upgrade

September 4, 2010 – 5:23 pm
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iTunes for Windows must be one of the buggiest, most poorly written applications out there. In terms of wasted months of your life it definitely ranks up there with Lotus Notes and Media Player 12. I don’t know how well iTunes works on a Mac (I like computer mice with twenty buttons, so I never was a big Mac fan), but I think I read somewhere that iTunes for Windows is the leading cause of suicides among iPhone owners.

Server and Network Monitoring with iPhone

February 25, 2010 – 6:53 pm
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What is a Unix sysadmin doing with an iPhone, you ask? It was a birthday present, if that’s all right with you. I know, I should have gotten something odd with a beta version of …

iPhone Photography: Making Photos Better

September 17, 2009 – 9:05 pm
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The is the first installment of the three-part review of the better photo apps for iPhone. In the follow-up reviews we will look at artistic photo filters and panorama applications. If you don’t want to …

Great iPhone Apps

September 3, 2009 – 3:22 am
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As the new year approaches, chances are, you’ve made a promise to yourself to get into shape or at least be more health conscious in 2015. Luckily, you can do so by taking advantage of …

More Bad iPhone Apps

August 13, 2009 – 1:19 am
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This is the second part of my review of iPhone apps unworthy of your ninety nine cents. You can read the first part here.
Certain applications are well-written and might have been quite useful, if …

Bad iPhone Apps

July 29, 2009 – 4:37 pm
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Oh quit your whining, you will say, they are just a couple bucks each, so no big loss if some iPhone apps turn out to be trash. True, but they are so addictive. My first …

iPhone: No Clicking Sound

July 16, 2009 – 4:58 am
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Many long-time iPhone users are familiar with the mystery of disappearing keyboard clicking sounds (among other sound effects). Here are a few things you can try before you take your fruity phone back to the …