base-4.4.1.0: Basic libraries

Portabilitynon-portable
Stabilityinternal
Maintainer[email protected]

GHC.Foreign

Contents

Description

Foreign marshalling support for CStrings with configurable encodings

Synopsis

C strings with a configurable encoding

peekCString :: TextEncoding -> CString -> IO StringSource

Marshal a NUL terminated C string into a Haskell string.

peekCStringLen :: TextEncoding -> CStringLen -> IO StringSource

Marshal a C string with explicit length into a Haskell string.

newCString :: TextEncoding -> String -> IO CStringSource

Marshal a Haskell string into a NUL terminated C string.

  • the Haskell string may not contain any NUL characters
  • new storage is allocated for the C string and must be explicitly freed using free or finalizerFree.

newCStringLen :: TextEncoding -> String -> IO CStringLenSource

Marshal a Haskell string into a C string (ie, character array) with explicit length information.

  • new storage is allocated for the C string and must be explicitly freed using free or finalizerFree.

withCString :: TextEncoding -> String -> (CString -> IO a) -> IO aSource

Marshal a Haskell string into a NUL terminated C string using temporary storage.

  • the Haskell string may not contain any NUL characters
  • the memory is freed when the subcomputation terminates (either normally or via an exception), so the pointer to the temporary storage must not be used after this.

withCStringLen :: TextEncoding -> String -> (CStringLen -> IO a) -> IO aSource

Marshal a Haskell string into a C string (ie, character array) in temporary storage, with explicit length information.

  • the memory is freed when the subcomputation terminates (either normally or via an exception), so the pointer to the temporary storage must not be used after this.

charIsRepresentable :: TextEncoding -> Char -> IO BoolSource

Determines whether a character can be accurately encoded in a CString.

Pretty much anyone who uses this function is in a state of sin because whether or not a character is encodable will, in general, depend on the context in which it occurs.