(Cc: man page maintainer) On Sun, Mar 21, 2010 at 01:33:28AM -0700, Valery Reznic wrote: > --- On Sat, 3/20/10, David Newall <davidn@xxxxxxxxxxxxxxx> wrote: > > Valery Reznic wrote: > > > execve's man page state that script's interprtert > > > should not be interpreter itself: ... > > > To me it looks like execve and it's man page > > > disagree. Do you know is it new intended behaviour of execve > > > and just man page wasn't update or it's a bug in execve ? > > > > Code and man pages do sometimes disagree. I shan't > > address what the correct behaviour is, because if you ask > > three people you're sure to get four different answers, > > rather let's discuss what is desirable. Without > > looking at how it works, we observe that a.sh can be > > executed without error. If a.out were written in C it > > would qualify as an acceptable interpreter according to the > > man page, so why should it not qualify if it is > > interpreted? I think it's desirable that it does > > qualify. There could be sound reasons why only one > > level of interpreter can be invoked. Perhaps loading a > > script interpreter is done as an exception in exec, and it's > > too ugly to allow recursive exceptions. That would be > > a fair reason. But if there's no reason, then don't > > have the restriction*. Linux now apparently does > > permit interpreted interpreters, and I say that is the > > desirable result. > For some reason I tough that ENOEXEC for 'interpreted interpreter' is posix > requirement. But after closer look it appear to be only arbitrary restriction > now lifted in Linux. > > I had a look at the source http://tomoyo.sourceforge.jp/cgi-bin/lxr/source/fs/binfmt_misc.c > and it's obvious that 'interpreted interpreter' is intentional (and recursion depth is 4). > So, execve is behave as it should and only man page is lag behind. > Thank you for you help/ > > > Just curios - who use this feature in the real world and what for ? It seems to have been changed in commit bf2a9a39639b8b51377905397a5005f444e9a892. Maybe you could ask the author for details. Johannes -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
