scp(1) on macOS
The text 51d475e14f31, as Mac OS X 10.4.7.x86, Mac OS X 10.4.7.ppc, Mac OS X 10.4.6.x86, Mac OS X 10.4.6.ppc, Mac OS X 10.4.5.x86, Mac OS X 10.4.5.ppc, Mac OS X 10.4.4.x86, Mac OS X 10.4.4.ppc, Mac OS X 10.4.3, Mac OS X 10.4.2, Mac OS X 10.4.1, Mac OS X 10.4 shipped it.
secure copy (remote file copy program)
Flags it lists
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-c -
-i -
-l -
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-p -
-q -
-r -
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