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</script></head><body><div id="package-header"><ul class="links" id="page-menu"><li><a href="src/System-IO-Streams-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">io-streams-1.1.4.5: Simple, composable, and easy-to-use stream I/O</p></div><div id="content"><div id="module-header"><table class="info"><tr><th>Safe Haskell</th><td>Trustworthy</td></tr></table><p class="caption">System.IO.Streams.Handle</p></div><div id="table-of-contents"><p class="caption">Contents</p><ul><li><a href="#g:1">Handle conversions
</a></li><li><a href="#g:2">Standard system handles
</a></li></ul></div><div id="description"><p class="caption">Description</p><div class="doc"><p>Input and output streams for file <code><a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a></code>s.
</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"><a href="#v:handleToInputStream">handleToInputStream</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/System-IO.html#t:IO">IO</a> (<a href="System-IO-Streams-Internal.html#t:InputStream">InputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a>)</li><li class="src short"><a href="#v:handleToOutputStream">handleToOutputStream</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/System-IO.html#t:IO">IO</a> (<a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a>)</li><li class="src short"><a href="#v:inputStreamToHandle">inputStreamToHandle</a> :: <a href="System-IO-Streams-Internal.html#t:InputStream">InputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/System-IO.html#t:IO">IO</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a></li><li class="src short"><a href="#v:outputStreamToHandle">outputStreamToHandle</a> :: <a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/System-IO.html#t:IO">IO</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a></li><li class="src short"><a href="#v:streamPairToHandle">streamPairToHandle</a> :: <a href="System-IO-Streams-Internal.html#t:InputStream">InputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a> -> <a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/System-IO.html#t:IO">IO</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a></li><li class="src short"><a href="#v:stdin">stdin</a> :: <a href="System-IO-Streams-Internal.html#t:InputStream">InputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a></li><li class="src short"><a href="#v:stdout">stdout</a> :: <a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a></li><li class="src short"><a href="#v:stderr">stderr</a> :: <a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a></li></ul></div><div id="interface"><h1 id="g:1">Handle conversions
</h1><div class="top"><p class="src"><a name="v:handleToInputStream" class="def">handleToInputStream</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/System-IO.html#t:IO">IO</a> (<a href="System-IO-Streams-Internal.html#t:InputStream">InputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a>)<a href="src/System-IO-Streams-Handle.html#handleToInputStream" class="link">Source</a></p><div class="doc"><p>Converts a read-only handle into an <code><a href="System-IO-Streams-Internal.html#t:InputStream">InputStream</a></code> of strict <code><a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a></code>s.
</p><p>Note that the wrapped handle is <em>not</em> closed when it yields end-of-stream;
you can use <code><a href="System-IO-Streams-Combinators.html#t:atEndOfInput">atEndOfInput</a></code> to close the handle
if you would like this behaviour.
</p></div></div><div class="top"><p class="src"><a name="v:handleToOutputStream" class="def">handleToOutputStream</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/System-IO.html#t:IO">IO</a> (<a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a>)<a href="src/System-IO-Streams-Handle.html#handleToOutputStream" class="link">Source</a></p><div class="doc"><p>Converts a writable handle into an <code><a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a></code> of strict <code><a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a></code>s.
</p><p>Note that the wrapped handle is <em>not</em> closed when it receives end-of-stream;
you can use <code><a href="System-IO-Streams-Combinators.html#t:atEndOfOutput">atEndOfOutput</a></code> to close the
handle if you would like this behaviour.
</p></div></div><div class="top"><p class="src"><a name="v:inputStreamToHandle" class="def">inputStreamToHandle</a> :: <a href="System-IO-Streams-Internal.html#t:InputStream">InputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/System-IO.html#t:IO">IO</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a><a href="src/System-IO-Streams-Handle.html#inputStreamToHandle" class="link">Source</a></p><div class="doc"><p>Converts an <code><a href="System-IO-Streams-Internal.html#t:InputStream">InputStream</a></code> over bytestrings to a read-only <code><a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a></code>. Note
that the generated handle is opened unbuffered in binary mode (i.e. no
newline translation is performed).
</p><p>Note: the <code><a href="System-IO-Streams-Internal.html#t:InputStream">InputStream</a></code> passed into this function is wrapped in
<code><a href="System-IO-Streams-Internal.html#v:lockingInputStream">lockingInputStream</a></code> to make it thread-safe.
</p><p><em>Since: 1.0.2.0.</em>
</p></div></div><div class="top"><p class="src"><a name="v:outputStreamToHandle" class="def">outputStreamToHandle</a> :: <a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/System-IO.html#t:IO">IO</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a><a href="src/System-IO-Streams-Handle.html#outputStreamToHandle" class="link">Source</a></p><div class="doc"><p>Converts an <code><a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a></code> over bytestrings to a write-only <code><a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a></code>. Note
that the <code><a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a></code> will be opened in non-buffering mode; if you buffer the
<code><a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a></code> using the <code><a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a></code> buffering then <code>io-streams</code> will copy the
<code><a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a></code> buffer when sending <code><a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a></code> values to the output, which might
not be what you want. When the output buffer, if used, is flushed, an empty
string is written to the output, as is conventional throughout the
<code>io-streams</code> library for <code><a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a></code> output buffers.
</p><p>Note: the <code><a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a></code> passed into this function is wrapped in
<code><a href="System-IO-Streams-Internal.html#v:lockingOutputStream">lockingOutputStream</a></code> to make it thread-safe.
</p><p><em>Since: 1.0.2.0.</em>
</p></div></div><div class="top"><p class="src"><a name="v:streamPairToHandle" class="def">streamPairToHandle</a> :: <a href="System-IO-Streams-Internal.html#t:InputStream">InputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a> -> <a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a> -> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/System-IO.html#t:IO">IO</a> <a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a><a href="src/System-IO-Streams-Handle.html#streamPairToHandle" class="link">Source</a></p><div class="doc"><p>Converts a pair of <code><a href="System-IO-Streams-Internal.html#t:InputStream">InputStream</a></code> and <code><a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a></code> over bytestrings to a
read-write <code><a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle.html#t:Handle">Handle</a></code>.
</p><p>Note: the streams passed into this function are wrapped in
locking primitives to make them thread-safe.
</p><p><em>Since: 1.0.2.0.</em>
</p></div></div><h1 id="g:2">Standard system handles
</h1><div class="top"><p class="src"><a name="v:stdin" class="def">stdin</a> :: <a href="System-IO-Streams-Internal.html#t:InputStream">InputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a><a href="src/System-IO-Streams-Handle.html#stdin" class="link">Source</a></p><div class="doc"><p>An <code><a href="System-IO-Streams-Internal.html#t:InputStream">InputStream</a></code> for <code><a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle-FD.html#v:stdin">stdin</a></code>.
</p></div></div><div class="top"><p class="src"><a name="v:stdout" class="def">stdout</a> :: <a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a><a href="src/System-IO-Streams-Handle.html#stdout" class="link">Source</a></p><div class="doc"><p>An <code><a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a></code> for <code><a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle-FD.html#v:stdout">stdout</a></code>.
</p></div></div><div class="top"><p class="src"><a name="v:stderr" class="def">stderr</a> :: <a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a> <a href="/usr/share/doc/ghc/html/libraries/bytestring-0.10.0.2/Data-ByteString.html#t:ByteString">ByteString</a><a href="src/System-IO-Streams-Handle.html#stderr" class="link">Source</a></p><div class="doc"><p>An <code><a href="System-IO-Streams-Internal.html#t:OutputStream">OutputStream</a></code> for <code><a href="/usr/share/doc/ghc/html/libraries/base-4.6.0.1/GHC-IO-Handle-FD.html#v:stderr">stderr</a></code>.
</p></div></div></div></div><div id="footer"><p>Produced by <a href="http://www.haskell.org/haddock/">Haddock</a> version 2.13.2</p></div></body></html>
