is this error due to softlink?

[bsmile]

I tried to compile nlopt on virtualbox with linux guest linux mint 18.0 and host windows 7. The error from make gives

CMake Error: cmake_symlink_library: System Error: Read-only file system
CMake Error: cmake_symlink_library: System Error: Read-only file system
CMakeFiles/nlopt.dir/build.make recipe for target 'libnlopt.so.0.9.0' failed
make[2]: *** [libnlopt.so.0.9.0] Error 1
make[2]: *** Deleting file 'libnlopt.so.0.9.0'
CMakeFiles/Makefile2:67: recipe for target 'CMakeFiles/nlopt.dir/all' failed
make[1]: *** [CMakeFiles/nlopt.dir/all] Error 2
Makefile:160: recipe for target 'all' failed

Is this error related to use of softlink? How to resolve this issue in order to have a successful installation on virtualbox?

[socratis]

The only error I see is:

System Error: Read-only file system

and unless you tell us what that system is, and if as I suspect this is on a VirtualBox Shared Folder, I don't see what your question has to do with VirtualBox.

[bsmile]

It is indeed on a VirtualBox Shared Folder with full access for read and write. The compilation has reached 75% completion and then failed giving the error message posted. So it does not seem to me an access issue.

The error message seems to me quite like a symbolic link error by noting symlink in the error message. I heard that virtualbox is not able to handle symbolic link on a windows host, and thus am concerned that this is the cause.

[socratis]

VirtualBox's Shared Folders present a very simplified file system implementation, just enough to read/write files from/to the guest. Many applications can error when using Shared Folders, because they expect advanced features, for example file locking, access controls, etc., which don't exist as a concept for Shared Folders.

I would use a a true network share (SaMBa).

[bsmile]

Thanks for your input. I think you have the point. I just figured out that the error is related the symbolic link to be set up on the shared folder. After I move the source files to the internal file system of linux mint, the compilation is successful without any issue.

[socratis]

You should have a searchable PDF included with your installation (Help » Contents). If not, there's the on-line manual in PDF format, again searchable. Take advantage of that fact, and use it to search the PDF for the terms that interest you.

For example, in ch. 4.3 Shared Folders it says:

Oracle VM VirtualBox shared folders also support symbolic links, also called symlinks, under the following conditions:

• The host operating system must support symlinks. For example, a Mac OS X, Linux, or Oracle Solaris host is required.
• Currently only Linux and Oracle Solaris Guest Additions support symlinks
• For security reasons the guest OS is not allowed to create symlinks by default. If you trust the guest OS to not abuse the functionality, you can enable creation of symlinks for a shared folder as follows:

  • VBoxManage setextradata "VM name" VBoxInternal2/SharedFoldersEnableSymlinksCreate/sharename 1

You don't even satisfy the first condition...