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Create Global Variables DLL in C++

$250-750 USD

Completed
Posted about 9 years ago

$250-750 USD

Paid on delivery
To create a DLL in Microsoft Visual Studio 2012 using C, or C++ allowing multiple applications to share common memory using arrays and stacks for strings and numbers. DLL functions will be called by multiple concurrent applications. The method for sharing the data must be by using a memory mapped file or shared data segment or any other method which directly shares memory (RAM) (not a physical file on the hard drive). The DLL must be written as a standard Windows DLL (Windows Standard Calling Convention). It cannot be ActiveX or COM because it will be called by programs that do not support ActiveX but do support standard DLL’s. See attached for specifications and requirements.
Project ID: 7256431

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13 proposals
Remote project
Active 9 yrs ago

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Code is "Hawaii" Dear Sir/Madam I am an electrical and computer engineer, proficient in C/C++. I have also experience with memory mapped files and reading/writing arrays, strings and custom data types from/to binary files. I would like to address some of the requirements per the specifications: 1. There is the issue of increasing the size of stacks/arrays when needed (assume that each stack/array will have its own MMF). It is not possible to extend the size of a MMF after its creation. There are 2 solutions. The first one is similar to C/C++ reallocation (e.g. when increasing the size of a vector). A new MMF with the new greater size is create, the data from the old MMF are copied over and the old MMF is destroyed. Pro's: very straightforward. Con's: may be slow, impossible to perform if already high in RAM usage. The second one is to create a second MMF to be used as an extension. This means that the DLL must keep track of the different MMFs used for a single stack/array. Pro's: not slow. Con's: much trickier to implement, there may be bugs not easily detected. What are your thoughts on the above? 2. Execution speed will not be slowed down by increasingly large indexes. For numerical data, it is simple to calculate the required offset in memory for the requested index. For string data there will be a separate array with the offset for each string. 3. Concurrency will be achieved by named mutexes. Best Regards Alex
$250 USD in 5 days
5.0 (26 reviews)
5.3
5.3
13 freelancers are bidding on average $470 USD for this job
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Hello. I have large experience with DLLs, Visual Studio and memory mapped files .....................
$250 USD in 5 days
4.9 (1675 reviews)
7.7
7.7
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I HAVE READ THIS DOCUMENT CODE WORD IS “HAWAII” ====================================================
$500 USD in 5 days
5.0 (56 reviews)
7.1
7.1
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To Whom It May Concern: With more than 7 years working on industry and a year working as a full-time freelancer, I have successfully worked on many high profile tasks, which include, but not limited to: * Generation of clustered distributed testing systems and automation terminals for Fortune 500 clients. * Development of hardware interfaces for custom devices. * High speed/multithreaded mission critical embedded systems and standard commutation protocols. * Library Modifications. * System programming in Linux/Unix and Windows. * GUI and UI design development. * Networked connectivity and synchronization through TCP/IP and other industrial grade communication protocols. * Database connectivity (local and networked). * Web design * And others... Summed with my strong educational background, demonstrated versatility, certified knowledge and high-profile achievements, I am confident that I can get you where you want to go in your endeavors, at a price that it is convenient for you. I encourage you to see my CV (one of my portfolio items) to review my qualifications in more detail. I am confident that you will be able to see that I have the required qualifications and track record that show my capabilities and my ability to serve you. Regardless of your decision, I would like to wish you the best in this project. My best wishes and I look forward to your response and to start a long term business relation with you. Sincerely, Juan Pablo Rodriguez
$640 USD in 7 days
5.0 (14 reviews)
6.7
6.7
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HAWAII Hello, If you remember, we have worked once on a DLL project, here on freelancer. I checked your document and can use Pthreads and C++ to crete the DLL. The only hard part will be the resizing of the memory that will hold the shared data. I am thinking of something like buckets. Each bucket holds 1000 elements, when its filled, we allocate another one. Haven't thought much about it, but since you can't resize shared memory and don't wan't to create a bigger segment and copy the data from old one, i think the buckets are a good start.
$500 USD in 10 days
4.9 (300 reviews)
6.9
6.9
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I HAVE READ THIS DOCUMENT CODE WORD IS “HAWAII”
$250 USD in 3 days
5.0 (10 reviews)
5.2
5.2
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$833 USD in 5 days
5.0 (2 reviews)
4.3
4.3
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Hi, I'm Dmitry. I have good expirience in C/C++ & WinApi. Also I already work with shared memory in windows. It will be very interesting work for me what with hiqh quality. I'm new on this site so work rather for good feedback than money. We can negotiate about dedline and price. Best regards, Dmitry.
$277 USD in 14 days
5.0 (7 reviews)
4.4
4.4
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"HAWAII" Hello I read attached document. Before I made program like this. But I have a question. How is long maximum string length? If you have interest to me, please leave message. Sincerely, Zhang
$555 USD in 3 days
4.7 (12 reviews)
4.2
4.2
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I'm a professional low-level programmer with strong knowledge of C++ and x86 assembly. I've worked on Windows Platform a lot and I know the DLL's and EXE's format in details (PE). I've worked even on closed-source software so I believe that I can do this job easily. I've read the document and I'm providing it's keyword - “HAWAII”.
$277 USD in 2 days
5.0 (7 reviews)
3.3
3.3
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c++ is my strong point what you are looking for I have probably already figure out. I just need to test let me know .....
$750 USD in 10 days
0.0 (0 reviews)
0.0
0.0

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Flag of UNITED STATES
Sioux Falls, United States
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Member since May 17, 2003

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