Commands I've constructed illustrating their usage:

To copy a file on one machine (nemesis) over to the 3.5" diskette drive on
another machine, 
  cat /usr/lpp/bos.sysmgt/nim/methods/IPLROM.emulation \
  | rsh aix-test dd of=/dev/fd0 conv=sync bs=4k
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fuser /dev/hd3  to find which process (returns PID) is using some file system.
  For example, you can't unmount /tmp.  fuser /dev/hd3 will return the PIDs
  of the /tmp users.
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find . -type d -print | xargs fs listacl | more

    - .       => was my home directory.
    - -type d => says find all the directories.
    - xargs fed all the directories into a fs listacl command
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To summarize disk usage, use du, eg du -k to show disk usage in kilobytes.
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To login on another machine as optionally another user,
     rlogin machine_name <-l other_user>
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(mwm &) - The parenthesis start a subshell before invoking the command.
          The ampersand puts the command in the background (ie, run as a
          child process and don't wait for return.

exec mwm - Overwrites the current shell process in memory with mwm and starts
           running mwm.

mwm - Run mwm as a child and wait for return.
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contrib/bin/wit shows you your system configuration.  
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To view a postscript file online, use ghostview.
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The difference between set (by itself) and env (by itself) is that set tells
     you about all your environment variables for this shell.  env tells you
     about all your environment variables that will be inherited by a child
     process (i.e.  that have been exported).
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