Binary package “psmisc” in ubuntu lunar

utilities that use the proc file system

 This package contains miscellaneous utilities that use the proc FS:
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  - fuser: identifies processes that are using files or sockets.
  - killall: kills processes by name (e.g. "killall -HUP named").
  - peekfd: shows the data traveling over a file descriptor.
  - pstree: shows currently running processes as a tree.
  - prtstat: print the contents of /proc/<pid>/stat