-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Access to the BSD sysctl(3) interface
--   
--   This module provides efficient access to the BSD sysctl(3) interface
--   via the Haskell FFI.
--   
--   It allows to read and write both basic sysctl types, as well as
--   complex opaque types (typically C structures) described via Storable
--   instances.
@package bsd-sysctl
@version 1.0.3


-- | This module allows access to the BSD sysctl(3) interface via the
--   Haskell FFI.
--   
--   Convenience functions to read and write the usual sysctl types are
--   provided, as well as more advanced functions to handle binary values
--   given a suitable <a>Storable</a> instance. It is also possible to
--   retrieve data whose size changes at runtime with the
--   <a>sysctlPeekArray</a> function.
--   
--   On some platforms, there are sysctl nodes that accept parameters via
--   additional components in the OID (see for instance the "kern.proc.pid"
--   sysctl described in sysctl(3) on FreeBSD). The
--   <tt>sysctlNameToOidArgs</tt> makes it easy to query such nodes as
--   well.
--   
--   Nodes may be queried either by their OID as a list of integers, by
--   their binary OID for maximum speed, or by their names on platforms
--   that support it.
module System.BSD.Sysctl

-- | The class of types that can be used to identify a sysctl node.
class SysctlKey k

-- | An efficient representation of a sysctl <a>OID</a> for maximum
--   performance.
data OID

-- | Prepare an <a>OID</a> for later use.
sysctlPrepareOid :: [Int32] -> IO OID

-- | Extract the list of integers contained in an <a>OID</a>.
sysctlExtractOid :: OID -> IO [Int32]

-- | Read a signed integer from a sysctl (the C int type).
sysctlReadInt :: (SysctlKey k) => k -> IO Int32

-- | Read an unsigned integer from a sysctl (the C unsigned int type).
sysctlReadUInt :: (SysctlKey k) => k -> IO Word32

-- | Read a signed long integer from a sysctl (the C long type).
sysctlReadLong :: (SysctlKey k) => k -> IO Int32

-- | Read an unsigned long integer from a sysctl (the C unsigned long
--   type).
sysctlReadULong :: (SysctlKey k) => k -> IO Word32

-- | Read a signed 64-bit integer from a sysctl.
sysctlReadQuad :: (SysctlKey k) => k -> IO Int64

-- | Read an unsigned 64-bit integer from a sysctl.
sysctlReadUQuad :: (SysctlKey k) => k -> IO Word64

-- | Read a string from a sysctl. If the string can possibly change with
--   time, use <a>sysctlPeekArray</a> for characters instead.
sysctlReadString :: (SysctlKey k) => k -> IO String

-- | Read a storable value from a sysctl node. This is useful to read
--   binary values such as C structures, otherwise the ad-hoc reading
--   functions should be used instead.
sysctlPeek :: (SysctlKey k, Storable a) => k -> IO a

-- | Like <a>sysctlPeek</a>, but allows to retrieve a list of elements
--   whose length can possibly change at runtime.
sysctlPeekArray :: (SysctlKey k, Storable a) => k -> IO [a]

-- | Write a signed integer to a sysctl (the C int type).
sysctlWriteInt :: (SysctlKey k) => k -> Int32 -> IO ()

-- | Write an unsigned integer to a sysctl (the C unsigned int type).
sysctlWriteUInt :: (SysctlKey k) => k -> Word32 -> IO ()

-- | Write a signed long integer to a sysctl (the C long type).
sysctlWriteLong :: (SysctlKey k) => k -> Int32 -> IO ()

-- | Write an unsigned long integer to a sysctl (the C unsigned long type).
sysctlWriteULong :: (SysctlKey k) => k -> Word32 -> IO ()

-- | Write a signed 64-bit integer to a sysctl.
sysctlWriteQuad :: (SysctlKey k) => k -> Int64 -> IO ()

-- | Write an unsigned 64-bit integer to a sysctl.
sysctlWriteUQuad :: (SysctlKey k) => k -> Word64 -> IO ()

-- | Write a string to a sysctl.
sysctlWriteString :: (SysctlKey k) => k -> String -> IO ()

-- | Write a storable value to a sysctl node. This is useful to write
--   binary values such as C structures, otherwise the ad-hoc writing
--   functions should be used instead.
sysctlPoke :: (SysctlKey k, Storable a) => k -> a -> IO ()
instance SysctlKey [Int32]
instance SysctlKey OID