operating-system

Static Memory allocation & Portability

I have read Static Memory Allocation are done during Compile time. Is the 'address allocated' used while generating executables ? Now, I am in doubt how the memory allocation is handled when the code executable is transferred completely onto a new system. I searched for it but I didn't get any answer on the internet. ...

Any info about book "Unix Internals: The New Frontiers" by Uresh Vahalia 2nd edition (Jan 2010)

This summer I'm getting into UNIX (mostly *BSD) development. I've graduate level knowledge about operating systems. I can also understand the code & read from here and there but the thing is I want to make most of my time. Reading books are best for this. From my search I found that these two books The Design and Implementation of th...

What Does an OS Actually Do?

What exactly does an operating system do? I know that operating systems can be programmed, in, for example, C++, but I previously believed that C++ programs must be run under an operating system? Can somebody please explain and give links? thanks in advance, ell ...

Is there Any Limit on stack memory!

I was going through one of the threads. A program crashed because It had declared an array of 10^6 locally inside a function. Reason being given was memory allocation failure on stack leads to crash. when same array was declared globally, it worked well.(memory on heap saved it). Now for the moment ,Let us suppose, stack grows downwar...

maximum memory which malloc can allocate!

I was trying to figure out how much memory I can malloc to maximum extent on my machine (1 Gb RAM 160 Gb HD Windows platform). I read that maximum memory malloc can allocate is limited to physical memory.(on heap) Also when a program exceeds consumption of memory to a certain level, the computer stops working because other applications ...

How To Create Your Own x86 Operating System for Modern PC Computers

I'd like to create a new operating system for x86 PC computers. I'd like it to be 64-bit but possibly run as 32-bit as well. I have these kinds of questions: What kinds of things do you start working on first? Knowing where to start in writing your own operating system seems to me to be a tricky subject, so I am interested in your inpu...

Would it be simply better to use the system's functions rather than use the language?

There are many scenarios where I've questioned PHP's performance with some of its functions, and whether I should build a complex class to handle specific things using its seemingly slow tools. For example, Complex regular expressions with sed and processing with awk would seemingly be exponential in performance rather than making PHP's...

How do I determine which C/C++ compiler to use?

Greetings, I am trying to figure out which C/C++ compiler to use. I found this list of C/C++ compilers at Wikipedia: http://en.wikipedia.org/wiki/List_of_compilers#C.2FC.2B.2B_compilers I am fairly certain that I want to go with an open source compiler. I feel that if it is open source then it will be a more complete compiler since ma...

Store value of os.system or os.popen

Hello, I want to grep the error's out of a log file and save the value as an error. When I use: errors = os.system("cat log.txt | grep 'ERROR' | wc -l") I get the return code that the command worked or not. When I use: errors = os.popen("cat log.txt | grep 'ERROR' | wc -l") I get what the command is trying to do. When I run this ...

Detect Windows 7 in .net

How can I detect Windows 7 (versions) in .net? What code can I use? ...

What is tha CAUSE of Error 523 and Error 200 in Blackberry handhelds

I'm Blackberry developer, customers using my application experiencing Error 523 and Error 200. Remedies to those errors are in first case - remove application, my application. In second case totally reload OS! This is very bad, and customers blame me! But this is I don't do anything illegal to make blackberry crash. I just used a lot of...

how to force operating system to give java more memory?

Hello, I've got problem with java jar files and memory. I use netbeans 6.7 to develop an application and this application need more memory to run because it converts another files. Whenever this application convert a 6-10 mb file, it'll crash. So I set netbeans VM Options : -Xms32m -Xmx256m and the application can convert 6-10mb files w...

Source code of System idle process

Just out of interest: what is the source code of system idle process? Which instructions are executed? How is CPU managed to enter power saving mode? ...

Detecting operating system or computer name through a Java servlet

I have a Java web app that I develop on a Windows machine and will deploy on a Unix machine. There are some file path settings and permissions details that differ on the two (and there is nothing I can do to change this). Is there some way of detecting which machine the app is sitting on (it's only one of two), either by detecting the o...

32/64 Bit Question

Here's my question. What is the best way to determine what bit architecture your app is running on? What I am looking to do: On a 64 bit server I want my app to read 64 bit datasources (stored in reg key Software\Wow6432Node\ODBC\ODBC.INI\ODBC Data Sources) and if its 32 bit I want to read 32 bit datasources, (i.e. Read from Software\OD...

Communication between parent and child

Hi every one ! I have a little problem. I have to code a simple C application that creat a process and his child (fork()) and I have to do an operation. Parent initialize the values and child calculate. I write this : #include <stdlib.h> #include <signal.h> #include <fcntl.h> #include <stdio.h> #include <unistd.h> typedef struct { ...

Get OS in c++ win32 for all versions of win?

How to get the OS version for all windows, at least the name for win95,98,me,xp,vista,7? Im using visual c++ 2010 and I want to include this feature in a pure win32 app. ...

Does the OS make a significant difference for Ruby Development ?

Hi, I have been working in Java for the past 4 years and I am currently switching over to Ruby. I am so excited about it and I feel good to finally get a hands on experience on a scripting language first time. The task assigned to me is to first pick a OS of my choice and setup a Ruby in it and study for 2 weeks. I have been developing ...

Dedicating all processor power to a task

Let's say we have a very processor-intensive task at hand which could be effectively parallelized. How can we dedicate all or almost all available processor power to performing that task? The task could be a variety of things, and iterative Fibonacci number generation that saves recorded numbers would be just one example. ...

What is the difference between kernel and user mode programming?

I would like to know how a kernel programmer thinks about memory vs user mode programmer. I would also like to know a few more differences between kernel programming and user mode programming. ...