How can you tell who has what files open?

[John Chambers]

In article <19168 at rpp386.cactus.org>, jfh at rpp386.cactus.org (John F Haugh II) writes:
> In article <1991Apr04.201719.3587 at ka3ovk> albers at ka3ovk.irs.gov.UUCP (Jon Albers) writes:
> >Is there a way to find out the process id of a process that has a file open?
> >Is there a way to list open files by process id, name, and/or inode?  I
> >want to be able to find out where the error starts.
> 
> Two commands will tell you has a file open - "fuser" and "ofiles".  "fuser"
> is standard with System V.  "ofiles" I believe is mostly a SunOS command,
> I'm sure someone from that universe can fill you in.
 
If your Sys/V is like this one, you may have to do  some  tweaking  to  get
fuser  to  a usable state.  When I typed it into a non-super-user window, I
got a "not found" message. Hunting about turned it up quickly, in /etc, but
when I typed /etc/fuser, the response was:
	/etc/fuser: /dev/kmem: Permission denied
Investigating further showed:
	-r-xr-xr-x   1 bin      bin        13404 Sep 20  1989 /etc/fuser
As a result, fuser as installed is only usable by a super-user; it  totally
fails  for  all  other  users.   I linked it into bin and modified it to be
setgid-kmem, and now it works.  Unfortunately, it still isn't exactly  what
I'd  call  a  user-friendly  program.   It  produces a process id.  This is
understandable, but for most users, this implies typing ps -ef and grepping
for the output of fuser. So I wrote a little script. At least I didn't have
to grovel through fuser's output with sed or awk  to  strip  away  assorted
junk;  they  were  programmer-friendly  if  not  user-friendly in having it
produce just the process id and nothing else.

Sometimes saying that a command is "standard with System V" is not quite all 
you need to know for a user to be able to make use of it.

-- 
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