Please let me know to overcome this problem for sucessfylly building and installing the Texgen Source code on Ubuntu 22.04 LTS (With gcc 11.4.0, VTK 6.3, g++ 11.4.0). Thanks in advance
The io.h is a header that one would include on Windows, while on *NIX hosts one would include unistd.h instead. For instance, from time to time I see the following condition in various projects:
Coming back to this TexGen project, their unistd.h looks strange and seems to be meant to be used on Windows (according to maintainers comments, and also because it includes io.h), while you are on a GNU/Linux host, and so it looks like you are including the headers from OctreeRefinement/include/ with that unistd.h among them, which is what fails the build.
Haven’t I just explained what is causing it, as I am guessing? That would be the first thing to try then. It might not be the actual reason, but at least something to start with.
Have you tried googling for the error text? Besides, it isn’t really about CMake at this point.
And since you said that you “used to” get this error, I take it that’s no longer the case?