IRC, freenode, #hurd, June 2010

<pochu> is there a way (POSIX or Hurdish) to get the corresponding file name for a fd or a hurd port?
<marcusb> there is a way
<pochu> marcusb: which one would that be?
<marcusb> I forgot
<marcusb> there is an implementation in libc
<marcusb> realpath has a similar job
<marcusb> but that's not what I mean
<marcusb> pochu: maybe I am misremembering.  But it was something where you keep looking up .. and list that directory, looking for the node with the ID of the node you had .. for
<marcusb> maybe it works only for directories
<marcusb> yeah
<marcusb> pochu: check the getcwd() implementation of libc
<marcusb> sysdeps/mach/hurd/getcwd.c
<marcusb> _hurd_canonicalize_directory_name_internal 
* pochu looks
<pochu> marcusb: interesting
<pochu> though that is for dirs, and doesn't seem to be extensible to files, as you cannot lookup for ".." under a file
<marcusb> right
<pochu> oh you already said that :)
<marcusb> actually, I am not sure that's correct
<marcusb> it's probably correct, but there is no reason why looking .. up on a file couldn't return the directory it's contianed in
<pochu> I don't know the interfaces or the Hurd internals very well yet, but it would look strange to me if you could do that
<marcusb> the hurd is strange
<pochu> it sounds like if you could `ls getcwd.c/..` to get sysdeps/mach/hurd/ :-)
<marcusb> yep
<pochu> ok. interesting
<marcusb> you wouldn't find "ls foo.zip/.." very strange, wouldn't you?
<pochu> I guess not if `ls foo.zip` listed the contents of foo.zip
<marcusb> there you go
<marcusb> or the other way round: would you be surprised if "cat somedir" would work?
<pochu> I think so. if it did, what would it do?
<marcusb> originally, cat dir would list the directory content!
<marcusb> in the old unix times
<pochu> I was surprised the first time I typed `vi somedir` by accident
<marcusb> and some early BSDs 
* pochu feels young :-)
<marcusb> he don't worry, I didn't see those times either
<marcusb> technically, files and directories are implemented in the same way in the hurd, they both are objects implementing the fs.defs interface
<marcusb> which combines file and directory operations
<marcusb> of course, files and directories implement those functions differently
<antrik> marcusb: do you know why this behavior (cat on directories) was changed?

IRC, freenode, #hurd, 2011-07-13

A related issue:

<braunr> rbraun@nordrassil:~$ vminfo $$ | wc -l
<braunr> 1039
<braunr> any idea why a shell would consume more than 1039 map entries ?
<braunr> (well, not more actually)
<braunr> even the kernel and ext2fs have around 100
<braunr> (the kernel has actually only 23, which is very good and expected)
<tschwinge> braunr: I agree that having some sort of debugging information
  for memory objects et al. would be quite hand.  To see where they're
  coming from, etc.
<braunr> tschwinge: this would require naming objects at the mach level
<braunr> e.g. when creating an object
<braunr> giving it the path of a file for example
<tschwinge> braunr: I have recently seen something (due to youpi fixing a
  bug) that bash is doing its own memory management.  Perhaps all these are
  such regions?
<tschwinge> braunr: For example, yes.
<braunr> what ?
<braunr> ?!
<tschwinge> braunr:
  http://lists.gnu.org/archive/html/bug-bash/2011-04/msg00097.html
<braunr> i see

Also see email thread starting at id:"20110714082216.GA8335@sceen.net".