Commands · Command
top
topShows a continuously updating, live view of running processes ranked by resource usage (CPU by default), refreshing every few seconds.
// PLATFORM NOTES
Linux
`-o` sorts by field, `-u` filters to one user, `-n` limits to N refresh cycles then exits.
macOS
BSD-derived `top` uses different flags for the same jobs — `-o` still sets the sort key, but `-U` (capital) filters by user instead of `-u`, and `-l <number>` sets the sample count instead of `-n`.
// FLAGS
-oLinux/macOS: choose the sort field, e.g. CPU or memory-uLinux only: filter to one user's processes-UmacOS only: filter to one user's processes — macOS's equivalent of Linux's -u-nLinux only: limit to N refresh cycles then exit-l <number>macOS only: set the number of samples to take then exit — macOS's equivalent of Linux's -n// EXAMPLE
top — opens the live process view; press q to quit, k to kill a process by PID.
// GOTCHA
top is interactive and takes over the terminal — running it in a script or piping its output requires batch mode (-b on Linux), otherwise it just hangs waiting for a terminal. The user-filter and sample-count flags also differ by platform: Linux uses -u/-n, while macOS's BSD-derived top uses -U/-l for the same two jobs — a flag copied straight from a Linux guide can silently do the wrong thing (or error) on a Mac.
// RELATED COMMANDS