docx converter -> doc, xlsx -> xls?

Question

linux

The essence of the problem: you need a converter from docx, xlsx to doc, xls, respectively. Under Linux, C++ is better for high speed. Tried through open office, but it turns out very slowly.

Answer 1

There is also the Aspose library for Java and .NET (http://www.aspose.com/). We use the Java version, it normally saves in different formats (in our tasks we need to save documents in xls, ods, pdf) . It is convenient that it is enough just to specify the extension when saving the file. BUT this is a paid solution, maybe you will find free solutions.

Answer 2

Can you write in C++?
www.libxl.com/ try to open xlsx with this library and save as xls
then tell us

Answer 3

What about the meaning?
Microsoft Office Compatibility Pack for Word, Excel, and PowerPoint
For end users (without the need for editing), doc(x) is generally harmful, there are PDF and ePub.