def self.sysctl_by_name(type, name)
oldp = FFI::Pointer::NULL
oldlenp = FFI::MemoryPointer.new(:size_t)
newp = FFI::Pointer::NULL
newlenp = 0
if type == :string
res = Libc.sysctlbyname(name, oldp, oldlenp, newp, newlenp)
return nil if res.negative?
else
oldlenp.write(:size_t, FFI.type_size(type))
end
oldp = FFI::MemoryPointer.new(:uint8_t, oldlenp.read(:size_t))
res = Libc.sysctlbyname(name, oldp, oldlenp, newp, newlenp)
return nil if res.negative?
case type
when :string
oldp.read_string
else
oldp.read(type)
end
end