[Development] QSharedMemory POSIX implementation

Calogero Mauceri mauceri at actgate.com
Wed Jul 9 16:17:38 CEST 2014

Hi all,

I find QSharedMemory very useful, and I'm extensively using it for cross 
platform IPC.

I noticed in the code (qsharedmemory_unix.cpp) there are two 
implementations for that class, one using System V IPC and the other 
using POSIX IPC (mmap). On both Linux and Mac versions of Qt, the System 
V primitives are used and there is no way to compile Qt using the POSIX 
implementation (-posix-ipc option is not available in configure).

Is there any reason why the System V implementation is preferred? I'd 
like to switch to the POSIX one to overcome limits in some platforms 
where the maximum shared memory allowed is only 4MB.


Calogero Mauceri
Software Engineer

Applied Coherent Technology Corporation (ACT)

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