Isn`t fashion to deliver the project file, is it?

[sept]

I did look into a few C++ Open Source projects. None of them did include a project file of some ide.

Why them get removed?

[CrazyNorman]

Most of them use AutoMake to build. A lot of them don't build it under something like Visual Studio, but prefer using the command line. Even if they did, AutoMake is guaranteed to work in more places than an IDE project file, as it configures things for the operating system.

[brewbuck]

I did look into a few C++ Open Source projects. None of them did include a project file of some ide.

There is no appropriate IDE choice when distributing a project in source code form. The develop cannot know what kind of IDE the end user has, if they have one at all. Therefore the build relies only on the most commonly present utilities -- the compiler, the shell, and the 'make' utility.

That's not to say that none of the developers use an IDE. But the IDE is typically not used to generate build systems, only for code editing and debugging.