Ausam/doc/man/man8/look.8

Find at most related files.
including files from this version of Unix. 
.th LOOK VIII "17 Mar 1979"
.sh NAME
look  \*-  scans system arrays for particular processes
.sh SYNOPSIS
.bd look
[
.bd \*-f
][
.bd \*-k
][
.bd \*-n
][
.bd \*-s
] file
.sh DESCRIPTION
.it Look
scans the system's inode, file, text, and proc arrays,
and the user areas, searching for all processes that
satisfy a given condition.  Normally, this condition
is that the process is active on the given mountable file system
(which may be specified either by the block\-device
name, or the file it is mounted on).
All processes that are executing shared text/data programs,
or have open files, or have their current directories, within
the specified file system, are printed out.
.s3
The options, which may appear in any order, are:
.s3
.lp +16 14
\fI-f\fB	All processes that are accessing the given file
(which need not be a file system)
are printed out.  The processes could be executing the
given file (if it is shared text/data),
or using it as the current directory, or accessing it
as a file.
.s3
.lp +16 14
\fI-k\fB	The processes found for either condition are signalled
instead of being printed out.  The current signal used is number 14
(System Termination).
.s3
.lp +16 14
\fI-n\fB	\fINcheck\fB is executed after \fIlook\fB is finished,
to look up the various inodes printed out.  As the number of arguments
the \fIncheck\fB is limited, only the first few inodes found will
be passed to \fIncheck\fB.
.s3
.lp +16 14
\fI-s\fB	The output is sorted in order of terminal identifying letter.
.s3
.i0
.dt
.it Look
is thus useful for finding (and perhaps killing) any processes that
are active on a disk that is to be unmounted.
It can also be used to assist in replacing sharable\-text programs
(such as the shell) by finding any active occurrences.
Note that processes that are printed out may be accessing other files
too \*- only those files of interest are printed out.
.s3
.sh FILES
/dev/mem, /dev/swap, /unix
.sh "SEE ALSO"
ncheck (VIII)
.sh DIAGNOSTICS
If no processes are found accessing an "active" inode,
an appropriate message is printed out.
.sh BUGS
.it Look
runs at very high priority, as it must take
a very quick snap\*-shot of the system arrays and user areas.
In a busy system, it is likely that these will be changing,
and the results may therefore be incorrect.  This is only
a problem when looking up user-areas (particularly if swapped\*-out),
where a consistency\*-check is made to ensure that the user
is still there!  If this test fails, the message `Retrying...'
is printed out.