Sophie: ghc-0:6.10.4-1mdv2010.0 i586

ghc-6.10.4-1mdv2010.0.i586.rpm

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>System.Posix.IO</TITLE
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>unix-2.3.2.0: POSIX functionality</TD
><TD CLASS="topbut"
><A HREF="index.html"
>Contents</A
></TD
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>Index</A
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><FONT SIZE="6"
>System.Posix.IO</FONT
></TD
><TD ALIGN="right"
><TABLE CLASS="narrow" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="infohead"
>Portability</TD
><TD CLASS="infoval"
>non-portable (requires POSIX)</TD
></TR
><TR
><TD CLASS="infohead"
>Stability</TD
><TD CLASS="infoval"
>provisional</TD
></TR
><TR
><TD CLASS="infohead"
>Maintainer</TD
><TD CLASS="infoval"
>libraries@haskell.org</TD
></TR
></TABLE
></TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="section4"
><B
>Contents</B
></TD
></TR
><TR
><TD
><DL
><DT
><A HREF="#1"
>Input / Output
</A
></DT
><DD
><DL
><DT
><A HREF="#2"
>Standard file descriptors
</A
></DT
><DT
><A HREF="#3"
>Opening and closing files
</A
></DT
><DT
><A HREF="#4"
>Reading/writing data
</A
></DT
><DT
><A HREF="#5"
>Seeking
</A
></DT
><DT
><A HREF="#6"
>File options
</A
></DT
><DT
><A HREF="#7"
>Locking
</A
></DT
><DT
><A HREF="#8"
>Pipes
</A
></DT
><DT
><A HREF="#9"
>Duplicating file descriptors
</A
></DT
><DT
><A HREF="#10"
>Converting file descriptors to/from Handles
</A
></DT
></DL
></DD
></DL
></TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="section1"
>Description</TD
></TR
><TR
><TD CLASS="doc"
>POSIX IO support.  These types and functions correspond to the unix
 functions open(2), close(2), etc.  For more portable functions
 which are more like fopen(3) and friends from stdio.h, see
 <A HREF="System-IO.html"
>System.IO</A
>.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="section1"
>Synopsis</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="decl"
><A HREF="#v%3AstdInput"
>stdInput</A
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AstdOutput"
>stdOutput</A
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AstdError"
>stdError</A
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="decl"
><SPAN CLASS="keyword"
>data</SPAN
>  <A HREF="#t%3AOpenMode"
>OpenMode</A
>  </TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="decl"
>= <A HREF="#v%3AReadOnly"
>ReadOnly</A
></TD
></TR
><TR
><TD CLASS="decl"
>| <A HREF="#v%3AWriteOnly"
>WriteOnly</A
></TD
></TR
><TR
><TD CLASS="decl"
>| <A HREF="#v%3AReadWrite"
>ReadWrite</A
></TD
></TR
></TABLE
></TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><SPAN CLASS="keyword"
>data</SPAN
>  <A HREF="#t%3AOpenFileFlags"
>OpenFileFlags</A
>  = <A HREF="#v%3AOpenFileFlags"
>OpenFileFlags</A
> {<TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="recfield"
><A HREF="#v%3Aappend"
>append</A
> :: <A HREF="../ghc-prim/GHC-Bool.html#t%3ABool"
>Bool</A
></TD
></TR
><TR
><TD CLASS="recfield"
><A HREF="#v%3Aexclusive"
>exclusive</A
> :: <A HREF="../ghc-prim/GHC-Bool.html#t%3ABool"
>Bool</A
></TD
></TR
><TR
><TD CLASS="recfield"
><A HREF="#v%3Anoctty"
>noctty</A
> :: <A HREF="../ghc-prim/GHC-Bool.html#t%3ABool"
>Bool</A
></TD
></TR
><TR
><TD CLASS="recfield"
><A HREF="#v%3AnonBlock"
>nonBlock</A
> :: <A HREF="../ghc-prim/GHC-Bool.html#t%3ABool"
>Bool</A
></TD
></TR
><TR
><TD CLASS="recfield"
><A HREF="#v%3Atrunc"
>trunc</A
> :: <A HREF="../ghc-prim/GHC-Bool.html#t%3ABool"
>Bool</A
></TD
></TR
></TABLE
>}</TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AdefaultFileFlags"
>defaultFileFlags</A
> :: <A HREF="System-Posix-IO.html#t%3AOpenFileFlags"
>OpenFileFlags</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AopenFd"
>openFd</A
> :: <A HREF="../base/System-IO.html#t%3AFilePath"
>FilePath</A
> -&gt; <A HREF="System-Posix-IO.html#t%3AOpenMode"
>OpenMode</A
> -&gt; <A HREF="../base/Data-Maybe.html#t%3AMaybe"
>Maybe</A
> <A HREF="../base/System-Posix-Types.html#t%3AFileMode"
>FileMode</A
> -&gt; <A HREF="System-Posix-IO.html#t%3AOpenFileFlags"
>OpenFileFlags</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AcreateFile"
>createFile</A
> :: <A HREF="../base/System-IO.html#t%3AFilePath"
>FilePath</A
> -&gt; <A HREF="../base/System-Posix-Types.html#t%3AFileMode"
>FileMode</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AcloseFd"
>closeFd</A
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../ghc-prim/GHC-Unit.html#t%3A%28%29"
>()</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AfdRead"
>fdRead</A
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="../base/System-Posix-Types.html#t%3AByteCount"
>ByteCount</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> (<A HREF="../base/Data-Char.html#t%3AString"
>String</A
>, <A HREF="../base/System-Posix-Types.html#t%3AByteCount"
>ByteCount</A
>)</TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AfdWrite"
>fdWrite</A
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="../base/Data-Char.html#t%3AString"
>String</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-Posix-Types.html#t%3AByteCount"
>ByteCount</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AfdSeek"
>fdSeek</A
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="../base/System-IO.html#t%3ASeekMode"
>SeekMode</A
> -&gt; <A HREF="../base/System-Posix-Types.html#t%3AFileOffset"
>FileOffset</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-Posix-Types.html#t%3AFileOffset"
>FileOffset</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="decl"
><SPAN CLASS="keyword"
>data</SPAN
>  <A HREF="#t%3AFdOption"
>FdOption</A
>  </TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="decl"
>= <A HREF="#v%3AAppendOnWrite"
>AppendOnWrite</A
></TD
></TR
><TR
><TD CLASS="decl"
>| <A HREF="#v%3ACloseOnExec"
>CloseOnExec</A
></TD
></TR
><TR
><TD CLASS="decl"
>| <A HREF="#v%3ANonBlockingRead"
>NonBlockingRead</A
></TD
></TR
><TR
><TD CLASS="decl"
>| <A HREF="#v%3ASynchronousWrites"
>SynchronousWrites</A
></TD
></TR
></TABLE
></TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AqueryFdOption"
>queryFdOption</A
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="System-Posix-IO.html#t%3AFdOption"
>FdOption</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../ghc-prim/GHC-Bool.html#t%3ABool"
>Bool</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AsetFdOption"
>setFdOption</A
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="System-Posix-IO.html#t%3AFdOption"
>FdOption</A
> -&gt; <A HREF="../ghc-prim/GHC-Bool.html#t%3ABool"
>Bool</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../ghc-prim/GHC-Unit.html#t%3A%28%29"
>()</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><SPAN CLASS="keyword"
>type</SPAN
> <A HREF="#t%3AFileLock"
>FileLock</A
> = (<A HREF="System-Posix-IO.html#t%3ALockRequest"
>LockRequest</A
>, <A HREF="../base/System-IO.html#t%3ASeekMode"
>SeekMode</A
>, <A HREF="../base/System-Posix-Types.html#t%3AFileOffset"
>FileOffset</A
>, <A HREF="../base/System-Posix-Types.html#t%3AFileOffset"
>FileOffset</A
>)</TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="decl"
><SPAN CLASS="keyword"
>data</SPAN
>  <A HREF="#t%3ALockRequest"
>LockRequest</A
>  </TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="decl"
>= <A HREF="#v%3AReadLock"
>ReadLock</A
></TD
></TR
><TR
><TD CLASS="decl"
>| <A HREF="#v%3AWriteLock"
>WriteLock</A
></TD
></TR
><TR
><TD CLASS="decl"
>| <A HREF="#v%3AUnlock"
>Unlock</A
></TD
></TR
></TABLE
></TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AgetLock"
>getLock</A
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="System-Posix-IO.html#t%3AFileLock"
>FileLock</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> (<A HREF="../base/Data-Maybe.html#t%3AMaybe"
>Maybe</A
> (<A HREF="../base/System-Posix-Types.html#t%3AProcessID"
>ProcessID</A
>, <A HREF="System-Posix-IO.html#t%3AFileLock"
>FileLock</A
>))</TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AsetLock"
>setLock</A
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="System-Posix-IO.html#t%3AFileLock"
>FileLock</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../ghc-prim/GHC-Unit.html#t%3A%28%29"
>()</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AwaitToSetLock"
>waitToSetLock</A
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="System-Posix-IO.html#t%3AFileLock"
>FileLock</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../ghc-prim/GHC-Unit.html#t%3A%28%29"
>()</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AcreatePipe"
>createPipe</A
> :: <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> (<A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
>, <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
>)</TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3Adup"
>dup</A
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AdupTo"
>dupTo</A
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AhandleToFd"
>handleToFd</A
> :: <A HREF="../base/System-IO.html#t%3AHandle"
>Handle</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3AfdToHandle"
>fdToHandle</A
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-IO.html#t%3AHandle"
>Handle</A
></TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="section1"
><A NAME="1"
><A NAME="1"
>Input / Output
</A
></A
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="section2"
><A NAME="2"
><A NAME="2"
>Standard file descriptors
</A
></A
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:stdInput"
><A NAME="v%3AstdInput"
></A
></A
><B
>stdInput</B
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:stdOutput"
><A NAME="v%3AstdOutput"
></A
></A
><B
>stdOutput</B
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:stdError"
><A NAME="v%3AstdError"
></A
></A
><B
>stdError</B
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="section2"
><A NAME="3"
><A NAME="3"
>Opening and closing files
</A
></A
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><SPAN CLASS="keyword"
>data</SPAN
>  <A NAME="t:OpenMode"
><A NAME="t%3AOpenMode"
></A
></A
><B
>OpenMode</B
>  </TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="section4"
>Constructors</TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="1" CELLPADDING="0"
><TR
><TD CLASS="arg"
><A NAME="v:ReadOnly"
><A NAME="v%3AReadOnly"
></A
></A
><B
>ReadOnly</B
></TD
><TD CLASS="rdoc"
></TD
></TR
><TR
><TD CLASS="arg"
><A NAME="v:WriteOnly"
><A NAME="v%3AWriteOnly"
></A
></A
><B
>WriteOnly</B
></TD
><TD CLASS="rdoc"
></TD
></TR
><TR
><TD CLASS="arg"
><A NAME="v:ReadWrite"
><A NAME="v%3AReadWrite"
></A
></A
><B
>ReadWrite</B
></TD
><TD CLASS="rdoc"
></TD
></TR
></TABLE
></TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><SPAN CLASS="keyword"
>data</SPAN
>  <A NAME="t:OpenFileFlags"
><A NAME="t%3AOpenFileFlags"
></A
></A
><B
>OpenFileFlags</B
>  </TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="ndoc"
>Correspond to some of the int flags from C's fcntl.h.
</TD
></TR
><TR
><TD CLASS="section4"
>Constructors</TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="5" CELLPADDING="0"
><TR
><TD CLASS="arg"
><A NAME="v:OpenFileFlags"
><A NAME="v%3AOpenFileFlags"
></A
></A
><B
>OpenFileFlags</B
></TD
><TD CLASS="rdoc"
></TD
></TR
><TR
><TD CLASS="body" COLSPAN="2"
><TABLE CLASS="vanilla" CELLSPACING="1" CELLPADDING="0"
><TR
><TD CLASS="arg"
><A NAME="v:append"
><A NAME="v%3Aappend"
></A
></A
><B
>append</B
> :: <A HREF="../ghc-prim/GHC-Bool.html#t%3ABool"
>Bool</A
></TD
><TD CLASS="rdoc"
>O_APPEND
</TD
></TR
><TR
><TD CLASS="arg"
><A NAME="v:exclusive"
><A NAME="v%3Aexclusive"
></A
></A
><B
>exclusive</B
> :: <A HREF="../ghc-prim/GHC-Bool.html#t%3ABool"
>Bool</A
></TD
><TD CLASS="rdoc"
>O_EXCL
</TD
></TR
><TR
><TD CLASS="arg"
><A NAME="v:noctty"
><A NAME="v%3Anoctty"
></A
></A
><B
>noctty</B
> :: <A HREF="../ghc-prim/GHC-Bool.html#t%3ABool"
>Bool</A
></TD
><TD CLASS="rdoc"
>O_NOCTTY
</TD
></TR
><TR
><TD CLASS="arg"
><A NAME="v:nonBlock"
><A NAME="v%3AnonBlock"
></A
></A
><B
>nonBlock</B
> :: <A HREF="../ghc-prim/GHC-Bool.html#t%3ABool"
>Bool</A
></TD
><TD CLASS="rdoc"
>O_NONBLOCK
</TD
></TR
><TR
><TD CLASS="arg"
><A NAME="v:trunc"
><A NAME="v%3Atrunc"
></A
></A
><B
>trunc</B
> :: <A HREF="../ghc-prim/GHC-Bool.html#t%3ABool"
>Bool</A
></TD
><TD CLASS="rdoc"
>O_TRUNC
</TD
></TR
></TABLE
></TD
></TR
></TABLE
></TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:defaultFileFlags"
><A NAME="v%3AdefaultFileFlags"
></A
></A
><B
>defaultFileFlags</B
> :: <A HREF="System-Posix-IO.html#t%3AOpenFileFlags"
>OpenFileFlags</A
></TD
></TR
><TR
><TD CLASS="doc"
>Default values for the <TT
><A HREF="System-Posix-IO.html#t%3AOpenFileFlags"
>OpenFileFlags</A
></TT
> type. False for each of
 append, exclusive, noctty, nonBlock, and trunc.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:openFd"
><A NAME="v%3AopenFd"
></A
></A
><B
>openFd</B
></TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="arg"
>:: <A HREF="../base/System-IO.html#t%3AFilePath"
>FilePath</A
></TD
><TD CLASS="rdoc"
></TD
></TR
><TR
><TD CLASS="arg"
>-&gt; <A HREF="System-Posix-IO.html#t%3AOpenMode"
>OpenMode</A
></TD
><TD CLASS="rdoc"
></TD
></TR
><TR
><TD CLASS="arg"
>-&gt; <A HREF="../base/Data-Maybe.html#t%3AMaybe"
>Maybe</A
> <A HREF="../base/System-Posix-Types.html#t%3AFileMode"
>FileMode</A
></TD
><TD CLASS="rdoc"
>Just x =&gt; creates the file with the given modes, Nothing =&gt; the file must exist.
</TD
></TR
><TR
><TD CLASS="arg"
>-&gt; <A HREF="System-Posix-IO.html#t%3AOpenFileFlags"
>OpenFileFlags</A
></TD
><TD CLASS="rdoc"
></TD
></TR
><TR
><TD CLASS="arg"
>-&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
><TD CLASS="rdoc"
></TD
></TR
><TR
><TD CLASS="ndoc" COLSPAN="2"
>Open and optionally create this file.  See System.Posix.Files
 for information on how to use the <TT
><A HREF="../base/System-Posix-Types.html#t%3AFileMode"
>FileMode</A
></TT
> type.
</TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:createFile"
><A NAME="v%3AcreateFile"
></A
></A
><B
>createFile</B
> :: <A HREF="../base/System-IO.html#t%3AFilePath"
>FilePath</A
> -&gt; <A HREF="../base/System-Posix-Types.html#t%3AFileMode"
>FileMode</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
></TR
><TR
><TD CLASS="doc"
>Create and open this file in WriteOnly mode.  A special case of
 <TT
><A HREF="System-Posix-IO.html#v%3AopenFd"
>openFd</A
></TT
>.  See System.Posix.Files for information on how to use
 the <TT
><A HREF="../base/System-Posix-Types.html#t%3AFileMode"
>FileMode</A
></TT
> type.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:closeFd"
><A NAME="v%3AcloseFd"
></A
></A
><B
>closeFd</B
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../ghc-prim/GHC-Unit.html#t%3A%28%29"
>()</A
></TD
></TR
><TR
><TD CLASS="doc"
>Close this file descriptor.  May throw an exception if this is an
 invalid descriptor.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="section2"
><A NAME="4"
><A NAME="4"
>Reading/writing data
</A
></A
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="doc"
>Programmers using the <TT
><A HREF="System-Posix-IO.html#v%3AfdRead"
>fdRead</A
></TT
> and <TT
><A HREF="System-Posix-IO.html#v%3AfdWrite"
>fdWrite</A
></TT
> API should be aware that
 EAGAIN exceptions may occur for non-blocking IO!
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:fdRead"
><A NAME="v%3AfdRead"
></A
></A
><B
>fdRead</B
></TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="arg"
>:: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
><TD CLASS="rdoc"
></TD
></TR
><TR
><TD CLASS="arg"
>-&gt; <A HREF="../base/System-Posix-Types.html#t%3AByteCount"
>ByteCount</A
></TD
><TD CLASS="rdoc"
>How many bytes to read
</TD
></TR
><TR
><TD CLASS="arg"
>-&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> (<A HREF="../base/Data-Char.html#t%3AString"
>String</A
>, <A HREF="../base/System-Posix-Types.html#t%3AByteCount"
>ByteCount</A
>)</TD
><TD CLASS="rdoc"
>The bytes read, how many bytes were read.
</TD
></TR
><TR
><TD CLASS="ndoc" COLSPAN="2"
>May throw an exception if this is an invalid descriptor.
</TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:fdWrite"
><A NAME="v%3AfdWrite"
></A
></A
><B
>fdWrite</B
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="../base/Data-Char.html#t%3AString"
>String</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-Posix-Types.html#t%3AByteCount"
>ByteCount</A
></TD
></TR
><TR
><TD CLASS="doc"
>May throw an exception if this is an invalid descriptor.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="section2"
><A NAME="5"
><A NAME="5"
>Seeking
</A
></A
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:fdSeek"
><A NAME="v%3AfdSeek"
></A
></A
><B
>fdSeek</B
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="../base/System-IO.html#t%3ASeekMode"
>SeekMode</A
> -&gt; <A HREF="../base/System-Posix-Types.html#t%3AFileOffset"
>FileOffset</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-Posix-Types.html#t%3AFileOffset"
>FileOffset</A
></TD
></TR
><TR
><TD CLASS="doc"
>May throw an exception if this is an invalid descriptor.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="section2"
><A NAME="6"
><A NAME="6"
>File options
</A
></A
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><SPAN CLASS="keyword"
>data</SPAN
>  <A NAME="t:FdOption"
><A NAME="t%3AFdOption"
></A
></A
><B
>FdOption</B
>  </TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="section4"
>Constructors</TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="1" CELLPADDING="0"
><TR
><TD CLASS="arg"
><A NAME="v:AppendOnWrite"
><A NAME="v%3AAppendOnWrite"
></A
></A
><B
>AppendOnWrite</B
></TD
><TD CLASS="rdoc"
>O_APPEND
</TD
></TR
><TR
><TD CLASS="arg"
><A NAME="v:CloseOnExec"
><A NAME="v%3ACloseOnExec"
></A
></A
><B
>CloseOnExec</B
></TD
><TD CLASS="rdoc"
>FD_CLOEXEC
</TD
></TR
><TR
><TD CLASS="arg"
><A NAME="v:NonBlockingRead"
><A NAME="v%3ANonBlockingRead"
></A
></A
><B
>NonBlockingRead</B
></TD
><TD CLASS="rdoc"
>O_NONBLOCK
</TD
></TR
><TR
><TD CLASS="arg"
><A NAME="v:SynchronousWrites"
><A NAME="v%3ASynchronousWrites"
></A
></A
><B
>SynchronousWrites</B
></TD
><TD CLASS="rdoc"
>O_SYNC
</TD
></TR
></TABLE
></TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:queryFdOption"
><A NAME="v%3AqueryFdOption"
></A
></A
><B
>queryFdOption</B
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="System-Posix-IO.html#t%3AFdOption"
>FdOption</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../ghc-prim/GHC-Bool.html#t%3ABool"
>Bool</A
></TD
></TR
><TR
><TD CLASS="doc"
>May throw an exception if this is an invalid descriptor.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:setFdOption"
><A NAME="v%3AsetFdOption"
></A
></A
><B
>setFdOption</B
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="System-Posix-IO.html#t%3AFdOption"
>FdOption</A
> -&gt; <A HREF="../ghc-prim/GHC-Bool.html#t%3ABool"
>Bool</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../ghc-prim/GHC-Unit.html#t%3A%28%29"
>()</A
></TD
></TR
><TR
><TD CLASS="doc"
>May throw an exception if this is an invalid descriptor.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="section2"
><A NAME="7"
><A NAME="7"
>Locking
</A
></A
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><SPAN CLASS="keyword"
>type</SPAN
> <A NAME="t:FileLock"
><A NAME="t%3AFileLock"
></A
></A
><B
>FileLock</B
> = (<A HREF="System-Posix-IO.html#t%3ALockRequest"
>LockRequest</A
>, <A HREF="../base/System-IO.html#t%3ASeekMode"
>SeekMode</A
>, <A HREF="../base/System-Posix-Types.html#t%3AFileOffset"
>FileOffset</A
>, <A HREF="../base/System-Posix-Types.html#t%3AFileOffset"
>FileOffset</A
>)</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><SPAN CLASS="keyword"
>data</SPAN
>  <A NAME="t:LockRequest"
><A NAME="t%3ALockRequest"
></A
></A
><B
>LockRequest</B
>  </TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="section4"
>Constructors</TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="1" CELLPADDING="0"
><TR
><TD CLASS="arg"
><A NAME="v:ReadLock"
><A NAME="v%3AReadLock"
></A
></A
><B
>ReadLock</B
></TD
><TD CLASS="rdoc"
></TD
></TR
><TR
><TD CLASS="arg"
><A NAME="v:WriteLock"
><A NAME="v%3AWriteLock"
></A
></A
><B
>WriteLock</B
></TD
><TD CLASS="rdoc"
></TD
></TR
><TR
><TD CLASS="arg"
><A NAME="v:Unlock"
><A NAME="v%3AUnlock"
></A
></A
><B
>Unlock</B
></TD
><TD CLASS="rdoc"
></TD
></TR
></TABLE
></TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:getLock"
><A NAME="v%3AgetLock"
></A
></A
><B
>getLock</B
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="System-Posix-IO.html#t%3AFileLock"
>FileLock</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> (<A HREF="../base/Data-Maybe.html#t%3AMaybe"
>Maybe</A
> (<A HREF="../base/System-Posix-Types.html#t%3AProcessID"
>ProcessID</A
>, <A HREF="System-Posix-IO.html#t%3AFileLock"
>FileLock</A
>))</TD
></TR
><TR
><TD CLASS="doc"
>May throw an exception if this is an invalid descriptor.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:setLock"
><A NAME="v%3AsetLock"
></A
></A
><B
>setLock</B
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="System-Posix-IO.html#t%3AFileLock"
>FileLock</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../ghc-prim/GHC-Unit.html#t%3A%28%29"
>()</A
></TD
></TR
><TR
><TD CLASS="doc"
>May throw an exception if this is an invalid descriptor.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:waitToSetLock"
><A NAME="v%3AwaitToSetLock"
></A
></A
><B
>waitToSetLock</B
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="System-Posix-IO.html#t%3AFileLock"
>FileLock</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../ghc-prim/GHC-Unit.html#t%3A%28%29"
>()</A
></TD
></TR
><TR
><TD CLASS="doc"
>May throw an exception if this is an invalid descriptor.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="section2"
><A NAME="8"
><A NAME="8"
>Pipes
</A
></A
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:createPipe"
><A NAME="v%3AcreatePipe"
></A
></A
><B
>createPipe</B
> :: <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> (<A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
>, <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
>)</TD
></TR
><TR
><TD CLASS="doc"
>The <TT
><A HREF="System-Posix-IO.html#v%3AcreatePipe"
>createPipe</A
></TT
> function creates a pair of connected file
 descriptors. The first component is the fd to read from, the second
 is the write end.  Although pipes may be bidirectional, this
 behaviour is not portable and programmers should use two separate
 pipes for this purpose.  May throw an exception if this is an
 invalid descriptor.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="section2"
><A NAME="9"
><A NAME="9"
>Duplicating file descriptors
</A
></A
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:dup"
><A NAME="v%3Adup"
></A
></A
><B
>dup</B
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
></TR
><TR
><TD CLASS="doc"
>May throw an exception if this is an invalid descriptor.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:dupTo"
><A NAME="v%3AdupTo"
></A
></A
><B
>dupTo</B
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
></TR
><TR
><TD CLASS="doc"
>May throw an exception if this is an invalid descriptor.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="section2"
><A NAME="10"
><A NAME="10"
>Converting file descriptors to/from Handles
</A
></A
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:handleToFd"
><A NAME="v%3AhandleToFd"
></A
></A
><B
>handleToFd</B
> :: <A HREF="../base/System-IO.html#t%3AHandle"
>Handle</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TD
></TR
><TR
><TD CLASS="doc"
>Extracts the <TT
><A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TT
> from a <TT
><A HREF="../base/System-IO.html#t%3AHandle"
>Handle</A
></TT
>.  This function has the side effect
 of closing the <TT
><A HREF="../base/System-IO.html#t%3AHandle"
>Handle</A
></TT
> and flushing its write buffer, if necessary.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:fdToHandle"
><A NAME="v%3AfdToHandle"
></A
></A
><B
>fdToHandle</B
> :: <A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
> -&gt; <A HREF="../base/System-IO.html#t%3AIO"
>IO</A
> <A HREF="../base/System-IO.html#t%3AHandle"
>Handle</A
></TD
></TR
><TR
><TD CLASS="doc"
><P
>Converts an <TT
><A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TT
> into a <TT
><A HREF="../base/System-IO.html#t%3AHandle"
>Handle</A
></TT
> that can be used with the
 standard Haskell IO library (see <A HREF="System-IO.html"
>System.IO</A
>).  
</P
><P
>GHC only: this function has the side effect of putting the <TT
><A HREF="../base/System-Posix-Types.html#t%3AFd"
>Fd</A
></TT
>
 into non-blocking mode (<TT
>O_NONBLOCK</TT
>) due to the way the standard
 IO library implements multithreaded I/O.
</P
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="botbar"
>Produced by <A HREF="http://www.haskell.org/haddock/"
>Haddock</A
> version 2.4.2</TD
></TR
></TABLE
></BODY
></HTML
>