[$] The shrinking role of ETXTBSY

Unix-like systems abound with ways to confuse new users, many of which havebeen present since long before Linux entered the scene. One consistentsource of befuddlement is the "text file is busy" (ETXTBSY) errormessage that is delivered in response to an attempt to overwrite anexecutable image file. Linux is far less likely to deliverETXTBSY results than it once was, but they do still happen onoccasion. Recent work to simplify the mechanism behind ETXTBSYhas raised a more fundamental question: does this error check have anyvalue at all?