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

one use

	golang.org/x/sys/unix (current package)
		zerrors_linux.go#L2473: 	PROCFS_IOCTL_MAGIC                          = 'f'

The pages are generated with Golds v0.7.6. (GOOS=linux GOARCH=amd64)