/usr/lib/help/sys_system is in scheme9 2013.11.26-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 | S9 EXT (sys:system string) ==> integer
Run the command STRING and return its exit status.
(sys:system "ls") ==> 0
(sys:system "ls nonexistent") ==> 1
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