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1. readExactly :: Int -> InputStream ByteString -> IO ByteString

   io-streams	System.IO.Streams.ByteString

   Reads an n-byte ByteString from an input stream. Throws a ReadTooShortException if fewer than n bytes were available. Example:

   ghci> Streams.fromList ["long string"] >>= Streams.readExactly 6
   "long s"
   ghci> Streams.fromList ["short"] >>= Streams.readExactly 6
   *** Exception: Short read, expected 6 bytes
   

2. readProcess :: FilePath -> [String] -> String -> IO String

   io-streams	System.IO.Streams.Process

   readProcess forks an external process, reads its standard output strictly, blocking until the process terminates, and returns the output string. The external process inherits the standard error. If an asynchronous exception is thrown to the thread executing readProcess, the forked process will be terminated and readProcess will wait (block) until the process has been terminated. Output is returned strictly, so this is not suitable for launching processes that require interaction over the standard file streams. This function throws an IOError if the process ExitCode is anything other than ExitSuccess. If instead you want to get the ExitCode then use readProcessWithExitCode. Users of this function should compile with -threaded if they want other Haskell threads to keep running while waiting on the result of readProcess.

   > readProcess "date" [] []
   "Thu Feb  7 10:03:39 PST 2008\n"
   

   The arguments are:
   • The command to run, which must be in the $PATH, or an absolute or relative path
   • A list of separate command line arguments to the program. See RawCommand for further discussion of Windows semantics.
   • A string to pass on standard input to the forked process.

3. readProcessWithExitCode :: FilePath -> [String] -> String -> IO (ExitCode, String, String)

   io-streams	System.IO.Streams.Process

   readProcessWithExitCode is like readProcess but with two differences:

   • it returns the ExitCode of the process, and does not throw any exception if the code is not ExitSuccess.
   • it reads and returns the output from process' standard error handle, rather than the process inheriting the standard error handle.
   On Unix systems, see waitForProcess for the meaning of exit codes when the process died as the result of a signal.

4. readFromPathPiece :: Read s => Text -> Maybe s

   path-pieces	Web.PathPieces

   A function for helping generate free PathPiece instances for enumeration data types that have derived Read and Show instances. Intended to be used like this:

   data MyData = Foo | Bar | Baz
   deriving (Read,Show)
   instance PathPiece MyData where
   fromPathPiece = readFromPathPiece
   toPathPiece = showToPathPiece
   

   Since 0.2.1.

5. readWriteMode :: TransactionMode -> !ReadWriteMode

   postgresql-simple	Database.PostgreSQL.Simple.Transaction

   No documentation available.

6. readSettingsFile :: Maybe FilePath -> String -> IO (FilePath, Maybe String)

   hlint	Language.Haskell.HLint

   Given a directory (or Nothing to imply getHLintDataDir), and a module name (e.g. HLint.Default), find the settings file associated with it, returning the name of the file, and (optionally) the contents. This function looks for all settings files starting with HLint. in the directory argument, and all other files relative to the current directory.

7. readFileBinary :: MonadIO m => FilePath -> m ByteString

   rio	RIO

   Same as readFile, but generalized to MonadIO

8. readFileUtf8 :: MonadIO m => FilePath -> m Text

   rio	RIO

   Read a file in UTF8 encoding, throwing an exception on invalid character encoding. This function will use OS-specific line ending handling.

9. readSomeRef :: MonadIO m => SomeRef a -> m a

   rio	RIO

   Read from a SomeRef

10. readURef :: (PrimMonad m, Unbox a) => URef (PrimState m) a -> m a

    rio	RIO

    Read the value in a URef

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