A dynamic link library (DLL) is an executable file that acts as a shared library of functions. Dynamic linking provides a way for a process to call a function that is not part of its executable code. The executable code for the function is located in a DLL, which contains one or more functions that are compiled, linked, and stored separately from the processes that use them. Multiple applications can simultaneously access the contents of a single copy of a DLL in memory. DLL support has been provided in TDL for quite a while. The focus was primarily on extending Tally for bringing in capabilities which could not be achieved within Tally. ‘CallDLLFunction’ allowed calling native/unmanaged DLLs which were written and compiled in C++.
In further releases, this moved a step further where the support was extended to use Plug-In and Activex Plug-In, where the XML output from the DLL could be used as a data source in the collection artefact, and thereby, consumed in TDL. This paved the way for new possibilities on extending Tally as per customer needs, which required interactions with external hardware, etc. However, this required changes in the DLL as per the processing capabilities of the collection. The XML output from the collection had to be necessarily from a function within DLL which had to be named mandatorily as TDLCollection within the DLLClass.
The Component Object Model (COM) is a component software architecture that allows applications and systems to be built from components supplied by different software vendors. COM is the underlying architecture that forms the foundation for higher level software services. These DLLs provide the standard benefits of shared libraries. Component Object Model (COM) was introduced by Microsoft to enable inter process communication and dynamic object creation across a varied range of programming languages. In other words, objects can be implemented in environments seamlessly different from the one in which they are created.This technology specifies manipulation of data associated with objects through an Interface. A COM interface refers to a predefined group of related functions that a COM class implements.The object implements the interface by using the code that implements each method of the interface, and provides COM binary-compliant pointers to those functions, to the COM library. COM then makes those functions available to the requesting clients.
COM DLL Support will pave the way for providing features like ‘Tally For Blind’ using the generic speech API provided by Microsoft. This Release comes with enhanced capabilities in the language to support COM DLL processing. A new definition type called COM Interface has been introduced for the same
In further releases, this moved a step further where the support was extended to use Plug-In and Activex Plug-In, where the XML output from the DLL could be used as a data source in the collection artefact, and thereby, consumed in TDL. This paved the way for new possibilities on extending Tally as per customer needs, which required interactions with external hardware, etc. However, this required changes in the DLL as per the processing capabilities of the collection. The XML output from the collection had to be necessarily from a function within DLL which had to be named mandatorily as TDLCollection within the DLLClass.
The Component Object Model (COM) is a component software architecture that allows applications and systems to be built from components supplied by different software vendors. COM is the underlying architecture that forms the foundation for higher level software services. These DLLs provide the standard benefits of shared libraries. Component Object Model (COM) was introduced by Microsoft to enable inter process communication and dynamic object creation across a varied range of programming languages. In other words, objects can be implemented in environments seamlessly different from the one in which they are created.This technology specifies manipulation of data associated with objects through an Interface. A COM interface refers to a predefined group of related functions that a COM class implements.The object implements the interface by using the code that implements each method of the interface, and provides COM binary-compliant pointers to those functions, to the COM library. COM then makes those functions available to the requesting clients.
COM DLL Support will pave the way for providing features like ‘Tally For Blind’ using the generic speech API provided by Microsoft. This Release comes with enhanced capabilities in the language to support COM DLL processing. A new definition type called COM Interface has been introduced for the same