Hi,
back in the old days, when using Visual source safe, i used to share projects in VSS between multiple solutions.
Doing this allowed me to open 2 visual studio solutions and both use the same code from the shared library.
i don't remember if the code was 2 (or more) times placed on my harddisk.
Is this also possible using SVN?
Yes, you can do this using the externals feature. Note that this is not quite the same thing as what was available in VSS, because in Subversion you can only include an entire subtree of a repository, instead of picking and choosing specific files.
The method VSS used was fragile and commits to one project could affect an unknown number of other projects. Don't even think about trying to get a compilable historical build out of VSS with shared files.
It is. SVN works by keeping a central repository where users/developers checkout code/projects onto their computers.
So each user has their own copy of the current version. They make their changes then when they sure all is working they checkin their changes. If another person has done the same thing for the same file and they checking first, then the 2nd person will have to merge their code over the 1st person's code.