"Kirill 'Big K' Katsnelson" <kkm(a)dtmx.com&gt; writes: I don't intend to quible but this is one of those things that interests me (meaning I am quibling). Under linux, it is marked as unmodifiable but can be removed (the inode is referenced by the (sort of) fd even though there is no directory entry). Under Solaris, the pages are marked copy-on-write so if an executable (not a script) is modified they don't affect the original[1]. --pete [1] Ok, I couldn't come up with a test for the copy-on-write and I'm only infering the behaviour.