Unix always had the tradition to give you enough rope so you can
hang yourself. OTOH, allowing such seemingly dangerous features
permit powerful tricks and simpler programming.
I always had the tradition of hating this attitude.
I'm a programmer. My program created a big file. Give me the POWER to *DELETE*
*MY* *FILE*!!
Too bad Unix doesn't give me enough rope to hang *it*, not just myself.
I've learned that "powerful" means "wrong". A feature is called "powerful" when:
* it's not directly related to what anyone would ever need,
* but it can be used to approximate useful things,
* although you won't get exactly what you want,
* and using it will take quite some time,
* and noone will understand how it works,
* and it will occasionally fail.
For example, a dialog saying "print pages x to y" is not powerful (does what you
want with no side effects and can't be used for anything else). A much more
powerful approach is to filter your document through a sed script, selecting
pages x to y, which will only take half a day and only occasionally fail. The
same approach can be used for mishandling a variety of problems - a clear proof
that it's powerful.
This is called an upgrade. The process won't crash because the code
is already loaded in memory. Upgrades are harder to handle on Win32
precisely because it doesn't allow (by default) to replace opened
files.
Yes it will. I'm pretty sure 'cause I've checked a few weeks ago. It won't crash
if you overwrite the executable. But it will crash if you overwrite a shared object.
By the way, I don't think all Unices do the same thing when it comes to files
mapped to the memory of a process.
