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</script></head><body><div id="package-header"><ul class="links" id="page-menu"><li><a href="src/Network-Socket-SendFile-Handle.html">Source</a></li><li><a href="index.html">Contents</a></li><li><a href="doc-index.html">Index</a></li></ul><p class="caption">sendfile-0.7.6: A portable sendfile library</p></div><div id="content"><div id="module-header"><p class="caption">Network.Socket.SendFile.Handle</p></div><div id="table-of-contents"><p class="caption">Contents</p><ul><li><a href="#g:1">Handle-based sendFiles
</a></li></ul></div><div id="description"><p class="caption">Description</p><div class="doc"><p>Handle-based versions of some of the functions exported by
Network.Socket.SendFile.
</p></div></div><div id="synopsis"><p id="control.syn" class="caption expander" onclick="toggleSection('syn')">Synopsis</p><ul id="section.syn" class="hide" onclick="toggleSection('syn')"><li class="src short"><span class="keyword">type</span> <a href="#t:ByteCount">ByteCount</a> = <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Prelude.html#t:Integer">Integer</a></li><li class="src short"><span class="keyword">type</span> <a href="#t:Offset">Offset</a> = <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Prelude.html#t:Integer">Integer</a></li><li class="src short"><span class="keyword">data</span> <a href="#t:Iter">Iter</a> <ul class="subs"><li>= <a href="#v:Sent">Sent</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Int.html#t:Int64">Int64</a> (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="Network-Socket-SendFile-Handle.html#t:Iter">Iter</a>) </li><li>| <a href="#v:WouldBlock">WouldBlock</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Int.html#t:Int64">Int64</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-Posix-Types.html#t:Fd">Fd</a> (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="Network-Socket-SendFile-Handle.html#t:Iter">Iter</a>) </li><li>| <a href="#v:Done">Done</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Int.html#t:Int64">Int64</a> </li></ul></li><li class="src short"><a href="#v:runIter">runIter</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="Network-Socket-SendFile-Handle.html#t:Iter">Iter</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Int.html#t:Int64">Int64</a></li><li class="src short"><a href="#v:sendFile">sendFile</a> :: <a href="/usr/share/doc/ghc/html/libraries/network-2.3.0.2/Network-Socket.html#t:Socket">Socket</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/GHC-IO-Handle.html#t:Handle">Handle</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="/usr/share/doc/ghc/html/libraries/ghc-prim-0.2.0.0/GHC-Unit.html#t:-40--41-">()</a></li><li class="src short"><a href="#v:sendFileIterWith">sendFileIterWith</a> :: (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="Network-Socket-SendFile-Handle.html#t:Iter">Iter</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> a) -> <a href="/usr/share/doc/ghc/html/libraries/network-2.3.0.2/Network-Socket.html#t:Socket">Socket</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/GHC-IO-Handle.html#t:Handle">Handle</a> -> <a href="Network-Socket-SendFile-Handle.html#t:ByteCount">ByteCount</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> a</li><li class="src short"><a href="#v:sendFile-39-">sendFile'</a> :: <a href="/usr/share/doc/ghc/html/libraries/network-2.3.0.2/Network-Socket.html#t:Socket">Socket</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/GHC-IO-Handle.html#t:Handle">Handle</a> -> <a href="Network-Socket-SendFile-Handle.html#t:Offset">Offset</a> -> <a href="Network-Socket-SendFile-Handle.html#t:ByteCount">ByteCount</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="/usr/share/doc/ghc/html/libraries/ghc-prim-0.2.0.0/GHC-Unit.html#t:-40--41-">()</a></li><li class="src short"><a href="#v:sendFileIterWith-39-">sendFileIterWith'</a> :: (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="Network-Socket-SendFile-Handle.html#t:Iter">Iter</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> a) -> <a href="/usr/share/doc/ghc/html/libraries/network-2.3.0.2/Network-Socket.html#t:Socket">Socket</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/GHC-IO-Handle.html#t:Handle">Handle</a> -> <a href="Network-Socket-SendFile-Handle.html#t:ByteCount">ByteCount</a> -> <a href="Network-Socket-SendFile-Handle.html#t:Offset">Offset</a> -> <a href="Network-Socket-SendFile-Handle.html#t:ByteCount">ByteCount</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> a</li></ul></div><div id="interface"><h1>Documentation</h1><div class="top"><p class="src"><span class="keyword">type</span> <a name="t:ByteCount" class="def">ByteCount</a> = <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Prelude.html#t:Integer">Integer</a><a href="src/Network-Socket-SendFile.html#ByteCount" class="link">Source</a></p><div class="doc"><p>The length (in bytes) which should be sent
</p></div></div><div class="top"><p class="src"><span class="keyword">type</span> <a name="t:Offset" class="def">Offset</a> = <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Prelude.html#t:Integer">Integer</a><a href="src/Network-Socket-SendFile.html#Offset" class="link">Source</a></p><div class="doc"><p>The file offset (in bytes) to start from
</p></div></div><div class="top"><p class="src"><span class="keyword">data</span> <a name="t:Iter" class="def">Iter</a> <a href="src/Network-Socket-SendFile-Iter.html#Iter" class="link">Source</a></p><div class="doc"><p>An iteratee for sendfile
</p><p>In general, a whole file is not sent by a single call to
sendfile(), but a series of calls which send successive pieces.
</p><p>The high-level API in this sendfile library has calls which will
send the entire file (or an entire requested offset+length), before
returning.
</p><p>However, there are instances where you want to be a bit more
involved in the sending loop. For example, if you want to tickle a
timeout after each chunk is sent or update a progress bar.
</p><p>The <code><a href="Network-Socket-SendFile-Handle.html#t:Iter">Iter</a></code> type gives you that power with out requiring you to
manage all the low-level details of the sendfile loop. The
interface is simple and consistant across all platforms.
</p><p>A call to sendfile() can result in three different states:
</p><ol><li> the requested number of bytes for that iteration was sent
successfully, there are more bytes left to send.
</li><li> some (possibly 0) bytes were sent, but the file descriptor
would now block if more bytes were written. There are more bytes
left to send.
</li><li> All the bytes were sent, and there is nothing left to send.
</li></ol><p>We handle these three cases by using a type with three
constructors:
</p><pre>
data Iter
= Sent Int64 (IO Iter)
| WouldBlock Int64 Fd (IO Iter)
| Done Int64
</pre><p>All three constructors provide an <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Int.html#t:Int64">Int64</a></code> which represents the
number of bytes sent for that particular iteration. (Not the total
byte count).
</p><p>The <code><a href="Network-Socket-SendFile-Handle.html#v:Sent">Sent</a></code> and <code><a href="Network-Socket-SendFile-Handle.html#v:WouldBlock">WouldBlock</a></code> constructors provide <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a></code> <code><a href="Network-Socket-SendFile-Handle.html#t:Iter">Iter</a></code> as their
final argument. Running this IO action will send the next block of
data.
</p><p>The <code><a href="Network-Socket-SendFile-Handle.html#v:WouldBlock">WouldBlock</a></code> constructor also provides the <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-Posix-Types.html#t:Fd">Fd</a></code> for the output
socket. You should not send anymore data until the <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-Posix-Types.html#t:Fd">Fd</a></code> would not
block. The easiest way to do that is to use <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Control-Concurrent.html#v:threadWaitWrite">threadWaitWrite</a></code> to
suspend the thread until the <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-Posix-Types.html#t:Fd">Fd</a></code> is available.
</p><p>A very simple function to drive the Iter might look like:
</p><pre>
runIter :: IO Iter -> IO ()
runIter iter =
do r <- iter
case r of
(Done _n) -> return ()
(Sent _n cont) -> runIter cont
(WouldBlock _n fd cont) ->
do threadWaitWrite fd
runIter cont
</pre><p>You would use it as the first argument to a *IterWith function, e.g.
</p><pre>
sendFileIterWith runIter outputSocket "/path/to/file" 2^16
</pre><p>The <code><a href="Network-Socket-SendFile-Handle.html#v:runIter">runIter</a></code> function provided by this module is similar, but also returns the total number of bytes sent.
</p><p>NOTE: You must not use the <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-Posix-Types.html#t:Fd">Fd</a></code> or the <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a></code> <code><a href="Network-Socket-SendFile-Handle.html#t:Iter">Iter</a></code> after the call
to *IterWith has returned. When the *IterWith functions return,
the file descriptors may be closed due to finalizers running.
</p></div><div class="subs constructors"><p class="caption">Constructors</p><table><tr><td class="src"><a name="v:Sent" class="def">Sent</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Int.html#t:Int64">Int64</a> (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="Network-Socket-SendFile-Handle.html#t:Iter">Iter</a>)</td><td class="doc"><p>number of bytes sent this pass and a continuation to send more
</p></td></tr><tr><td class="src"><a name="v:WouldBlock" class="def">WouldBlock</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Int.html#t:Int64">Int64</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-Posix-Types.html#t:Fd">Fd</a> (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="Network-Socket-SendFile-Handle.html#t:Iter">Iter</a>)</td><td class="doc"><p>number of bytes sent, Fd that blocked, continuation to send more. NOTE: The Fd should not be used outside the running of the Iter as it may be freed when the Iter is done
</p></td></tr><tr><td class="src"><a name="v:Done" class="def">Done</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Int.html#t:Int64">Int64</a></td><td class="doc"><p>number of bytes sent, no more to send
</p></td></tr></table></div></div><div class="top"><p class="src"><a name="v:runIter" class="def">runIter</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="Network-Socket-SendFile-Handle.html#t:Iter">Iter</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Int.html#t:Int64">Int64</a><a href="src/Network-Socket-SendFile-Iter.html#runIter" class="link">Source</a></p><div class="doc"><p>A simple function to drive the *IterWith functions.
It returns the total number of bytes sent.
</p></div></div><h1 id="g:1">Handle-based sendFiles
</h1><div class="top"><p class="src"><a name="v:sendFile" class="def">sendFile</a> :: <a href="/usr/share/doc/ghc/html/libraries/network-2.3.0.2/Network-Socket.html#t:Socket">Socket</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/GHC-IO-Handle.html#t:Handle">Handle</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="/usr/share/doc/ghc/html/libraries/ghc-prim-0.2.0.0/GHC-Unit.html#t:-40--41-">()</a><a href="src/Network-Socket-SendFile-Handle.html#sendFile" class="link">Source</a></p><div class="doc"><p>Simple sendFile - give it a Socket and a Handle, and it sends the entire
file through the socket.
</p><p>WARNING: This function will raise <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO-Error.html#t:IOError">IOError</a></code> <code>IllegalOperation</code>
if the <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/GHC-IO-Handle.html#t:Handle">Handle</a></code> is not for an <code>Fd</code>.
</p></div></div><div class="top"><p class="src"><a name="v:sendFileIterWith" class="def">sendFileIterWith</a> :: (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="Network-Socket-SendFile-Handle.html#t:Iter">Iter</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> a) -> <a href="/usr/share/doc/ghc/html/libraries/network-2.3.0.2/Network-Socket.html#t:Socket">Socket</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/GHC-IO-Handle.html#t:Handle">Handle</a> -> <a href="Network-Socket-SendFile-Handle.html#t:ByteCount">ByteCount</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> a<a href="src/Network-Socket-SendFile-Handle.html#sendFileIterWith" class="link">Source</a></p><div class="doc"><p>A more interactive version of sendFile, which accepts a callback function
in addition to the socket and handle. The callback will be called for each
chunk of data the sendFileIterWith function acts on.
</p><p>WARNING: This function will raise <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO-Error.html#t:IOError">IOError</a></code> <code>IllegalOperation</code>
if the <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/GHC-IO-Handle.html#t:Handle">Handle</a></code> is not for an <code>Fd</code>.
</p></div></div><div class="top"><p class="src"><a name="v:sendFile-39-" class="def">sendFile'</a> :: <a href="/usr/share/doc/ghc/html/libraries/network-2.3.0.2/Network-Socket.html#t:Socket">Socket</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/GHC-IO-Handle.html#t:Handle">Handle</a> -> <a href="Network-Socket-SendFile-Handle.html#t:Offset">Offset</a> -> <a href="Network-Socket-SendFile-Handle.html#t:ByteCount">ByteCount</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="/usr/share/doc/ghc/html/libraries/ghc-prim-0.2.0.0/GHC-Unit.html#t:-40--41-">()</a><a href="src/Network-Socket-SendFile-Handle.html#sendFile%27" class="link">Source</a></p><div class="doc"><p>A sendFile that allows the user to send a subset of the file associated
with the given handle.
</p><p>WARNING: This function will raise <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO-Error.html#t:IOError">IOError</a></code> <code>IllegalOperation</code>
if the <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/GHC-IO-Handle.html#t:Handle">Handle</a></code> is not for an <code>Fd</code>.
</p></div></div><div class="top"><p class="src"><a name="v:sendFileIterWith-39-" class="def">sendFileIterWith'</a> :: (<a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> <a href="Network-Socket-SendFile-Handle.html#t:Iter">Iter</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> a) -> <a href="/usr/share/doc/ghc/html/libraries/network-2.3.0.2/Network-Socket.html#t:Socket">Socket</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/GHC-IO-Handle.html#t:Handle">Handle</a> -> <a href="Network-Socket-SendFile-Handle.html#t:ByteCount">ByteCount</a> -> <a href="Network-Socket-SendFile-Handle.html#t:Offset">Offset</a> -> <a href="Network-Socket-SendFile-Handle.html#t:ByteCount">ByteCount</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO.html#t:IO">IO</a> a<a href="src/Network-Socket-SendFile-Handle.html#sendFileIterWith%27" class="link">Source</a></p><div class="doc"><p>A more powerful version of sendFileIterWith, which allows the sending of a
subset of the given file.
</p><p>WARNING: This function will raise <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/System-IO-Error.html#t:IOError">IOError</a></code> <code>IllegalOperation</code>
if the <code><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/GHC-IO-Handle.html#t:Handle">Handle</a></code> is not for an <code>Fd</code>.
</p></div></div></div></div><div id="footer"><p>Produced by <a href="http://www.haskell.org/haddock/">Haddock</a> version 2.9.2</p></div></body></html>
