32-bit

Just wondering if there is a restriction on the max memory that a C++ application uses I understand that this is 2GB - Is that correct? If a C++ app tries to request more then 2GB memory does this cause a memory crash? Final question - If the machine the C++ app is running on is already low on memory and a C++ app asks for 100MB of array (ie contiguous memory) will the OS accommodate this by using virtual memory? It will cause a dynamic memory allocation failure, which usually will make the resultant application crash, but technically, an application could be written to withstand this event.

Intel's 32-bit processors such as Pentium have 64-bit wide data bus and therefore fetch 8 bytes per access. Based on this, I'm assuming that the physical addresses that these processors emit on the address bus are always multiples of 8. Firstly, is this conclusion correct? Secondly, if it is correct, then one should align data structure members on an 8 byte boundary. But I've seen people using a 4-byte alignment instead on these processors. How can they be justified in doing so? jalf The usual rule of thumb (straight from Intels and AMD's optimization manuals) is that every data type should be

On Linux systems (either 32- or 64-bit), what is the size of pid_t , uid_t , and gid_t ? Dave #include <stdio.h> #include <sys/types.h> int main() { printf("pid_t: %zu\n", sizeof(pid_t)); printf("uid_t: %zu\n", sizeof(uid_t)); printf("gid_t: %zu\n", sizeof(gid_t)); } EDIT: Per popular request (and because, realistically, 99% of the people coming to this question are going to be running x86 or x86_64)... On an i686 and x86_64 (so, 32-bit and 64-bit) processor running Linux >= 3.0.0, the answer is: pid_t: 4 uid_t: 4 gid_t: 4 On intel architectures, sizes are defined in /usr/include/bits

From my experience with Windows 7 (64-bit) and Java, a 32-bit JRE uses less memory and runs significantly faster than a 64-bit JRE (provided you don't need or benefit from having a lot of memory). I imagine the same thing is true for Mac OSX (and other platforms) as well. I am currently running OSX Lion (v10.7), and I have installed the standard Java app. Under Java Preferences, I see "Java SE 6" from "Apple Inc." for both CPU-types "32-bit" and "64-bit" version "1.6.0_26-b03-383". I have changed the preferred order to put the 32-bit version on top of the 64-bit version, hoping that this would

How can I programmatically tell in C# if an unmanaged DLL file is x86 or x64? yoyoyoyosef Refer to the specifications . Here's a basic implementation: public static MachineType GetDllMachineType(string dllPath) { // See http://www.microsoft.com/whdc/system/platform/firmware/PECOFF.mspx // Offset to PE header is always at 0x3C. // The PE header starts with "PE\0\0" = 0x50 0x45 0x00 0x00, // followed by a 2-byte machine type field (see the document above for the enum). // FileStream fs = new FileStream(dllPath, FileMode.Open, FileAccess.Read); BinaryReader br = new BinaryReader(fs); fs.Seek(0x3c

I am new to programming and come from a non-CS background (no formal degree). I mostly program winforms using C#. I am confused about 32 bit and 64 bit.... I mean, have heard about 32 bit OS, 32 bit processor and based on which a program can have maximum memory. How it affects the speed of a program. There are lot more questions which keep coming to mind. I tried to go through some Computer Organization and Architecture books. But, either I am too dumb to understand what is written in there or the writers assume that the reader has some CS background. Can someone explain me these things in a

I have a 32-bit .so binary-only library and I have to generate 64-bit program that uses it. Is there a way to wrap or convert it, so it can be used with 64-bit program? No. You can't directly link to 32bit code inside of a 64bit program. The best option is to compile a 32bit (standalone) program that can run on your 64bit platform (using ia32) , and then use a form of inter-process communication to communicate to it from your 64bit program. Zan Lynx For an example of using IPC to run 32-bit plugins from 64-bit code, look at the open source NSPluginWrapper . It is possible, but not without some