const golang.org/x/sys/unix.SO_RCVBUFFORCE

one use

	golang.org/x/sys/unix (current package)
		zerrors_linux_amd64.go#L329: 	SO_RCVBUFFORCE                   = 0x21

The pages are generated with Golds v0.4.9. (GOOS=linux GOARCH=amd64)