CompiledDllHistory

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The compiled DLL is based on the work by 2012 Austen Conrad: (from net/Git/github.com/AustenConrad/mql4zmq/mql4zmq.c)

The reason for all of this is that MetaTrader is a visual basic application and therefore is written using the STDCALL calling convention while ZeroMQ dll EXPORT defaults to the standard C calling convention (CDECL). If not changed, a call to libzmq.dll from MetaTrader will result in the trading terminal crashing.

Therefore, this file generates mql4zmq.dll which wraps each call the zmq.h exports when compiled as libzmq.dll (i.e. each function that has ZMQ_EXPORT preceeding it) as a STDCALL instead (i.e. __stdcall via WINAPI definition).

Additionally, MetaTrader4 has limitations on datatypes and data structures that we attempt to resolve by having the wrapping function inputs being of a type and in a manner that will jive with MQL4.

To avoid naming collisions with the original zmq.h definitions we renamed our exported functions with 'mql4' appended to the beginning of the name. In the OTMql4Zmq.mqh we revert the names back to the original to reduce confusion when writing experts.

The source checked in to the src/mql4zmq directory has the very simple changes needed to run against ZeroMQ 4.0.x and is from: `git clone -b MQ_610_ZMQ_4 --single-branch https://github.com/ungratefulson/mql4zmq`

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