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$50 USD / hour
rockford, united states
$50 USD / hour
It's currently 2:40 AM here
Joined September 3, 2010
3 Recommendations

Mark O.


5.0 (26 reviews)
$50 USD / hour
rockford, united states
$50 USD / hour
Jobs Completed
On Budget
On Time
Repeat Hire Rate

Quality is a virtue of design

Primarily skills in performance programming, C++/C, Objective C, Fortran, Parallel Programming, pthreads, GUI development, Cocoa, JNI, and Network programming (TCP/IP, Encryption).Specialize in client/server applications over TCP/UDP sockets, UDP hole punching. Over 25 year experience in these: OS X, UNIX, Linux, Windows, Solaris. Also, specializing in License Management
Freelancer C Programmers United States

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Portfolio Items

This is sample code that comes with my product.  It allows you to activate your software over the internet.
SafeGuard LM Software Product Activation


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Showing 1 - 5 out of 26 reviews
Filter reviews by: 5.0
$55.00 USD
Well and good.
Flag of Alekhya P. @pallaalekhya93
8 years ago
$88.00 USD
Excellent work. Everything was delivered on time and exactly how I asked.
C Programming
Flag of Marlon L. @dmlangdonjr
8 years ago
$250.00 USD
Brillant, Completed in timely fashion and made sure everything was working as it should.
.NET Linux Software Architecture C++ Programming
Flag of Shane P. @androidfan1
9 years ago
$277.00 USD
If you are lucky enough to have repairman4 bid on your project, you should accept. Excellent communication and will continuously work until all project requirements are met.
C Programming Linux UNIX
Flag of Mer @fertuser2
9 years ago
$30.00 AUD
Awesome communication. Quality work. Highly recommended. Will definitely rehire in the future. repairman4 went out of his way to to help out and explain the final product. Thanks!
C Programming
Flag of Ima R. @imarotar2
9 years ago


Bachelors of Science

Rockford College, United States 1979 - 1984
(5 years)


Windows NT Internals

Microsoft Corp.
This was an intensive developer class taught by MS personnel in Redmond Washington. One primary objective was to show how to update running application servers in place without having to shut them down.


Automatic Software Updates over the Internet

Environmental Systems Research Institute, Inc.
Back in the late 90's I proposed having users installed software automatically updated over the internet. Back then it was a big deal because we were still coming in over dialup lines. None the less, higher speed internet connections were on the rise and I implemented an automatic software update utility that would be able to patch our software over the Internet. Of course, in todays world, this is expected behavior. No one even thinks about it anymore but at the time and with the much slower in

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Top Skills

C Programming 27 C++ Programming 12 Linux 11 UNIX 5 Mac OS 4

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