sam-t2/devtools/amd64/html/python/lib/module-posix.html

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>
<head>
<link rel="STYLESHEET" href="lib.css" type='text/css' />
<link rel="SHORTCUT ICON" href="../icons/pyfav.png" type="image/png" />
<link rel='start' href='../index.html' title='Python Documentation Index' />
<link rel="first" href="lib.html" title='Python Library Reference' />
<link rel='contents' href='contents.html' title="Contents" />
<link rel='index' href='genindex.html' title='Index' />
<link rel='last' href='about.html' title='About this document...' />
<link rel='help' href='about.html' title='About this document...' />
<link rel="next" href="module-pwd.html" />
<link rel="prev" href="unix.html" />
<link rel="parent" href="unix.html" />
<link rel="next" href="posix-large-files.html" />
<meta name='aesop' content='information' />
<title>8.1 posix -- The most common POSIX system calls</title>
</head>
<body>
<DIV CLASS="navigation">
<div id='top-navigation-panel' xml:id='top-navigation-panel'>
<table align="center" width="100%" cellpadding="0" cellspacing="2">
<tr>
<td class='online-navigation'><a rel="prev" title="8. Unix Specific Services"
  href="unix.html"><img src='../icons/previous.png'
  border='0' height='32'  alt='Previous Page' width='32' /></A></td>
<td class='online-navigation'><a rel="parent" title="8. Unix Specific Services"
  href="unix.html"><img src='../icons/up.png'
  border='0' height='32'  alt='Up One Level' width='32' /></A></td>
<td class='online-navigation'><a rel="next" title="8.1.1 Large File Support"
  href="posix-large-files.html"><img src='../icons/next.png'
  border='0' height='32'  alt='Next Page' width='32' /></A></td>
<td align="center" width="100%">Python Library Reference</td>
<td class='online-navigation'><a rel="contents" title="Table of Contents"
  href="contents.html"><img src='../icons/contents.png'
  border='0' height='32'  alt='Contents' width='32' /></A></td>
<td class='online-navigation'><a href="modindex.html" title="Module Index"><img src='../icons/modules.png'
  border='0' height='32'  alt='Module Index' width='32' /></a></td>
<td class='online-navigation'><a rel="index" title="Index"
  href="genindex.html"><img src='../icons/index.png'
  border='0' height='32'  alt='Index' width='32' /></A></td>
</tr></table>
<div class='online-navigation'>
<b class="navlabel">Previous:</b>
<a class="sectref" rel="prev" href="unix.html">8. Unix Specific Services</A>
<b class="navlabel">Up:</b>
<a class="sectref" rel="parent" href="unix.html">8. Unix Specific Services</A>
<b class="navlabel">Next:</b>
<a class="sectref" rel="next" href="posix-large-files.html">8.1.1 Large File Support</A>
</div>
<hr /></div>
</DIV>
<!--End of Navigation Panel-->

<H1><A NAME="SECTION0010100000000000000000">
8.1 <tt class="module">posix</tt> --
         The most common POSIX system calls</A>
</H1>

<P>
<A NAME="module-posix"></A>
<p class="availability">Availability: <span
 class="platform">Unix</span>.</p>

<P>
This module provides access to operating system functionality that is
standardized by the C Standard and the POSIX standard (a thinly
disguised <span class="Unix">Unix</span> interface).

<P>
<strong>Do not import this module directly.</strong>  Instead, import the
module <tt class="module"><a href="module-os.html">os</a></tt>, which provides a <em>portable</em> version of this
interface.  On <span class="Unix">Unix</span>, the <tt class="module"><a href="module-os.html">os</a></tt> module provides a superset of
the <tt class="module">posix</tt> interface.  On non-<span class="Unix">Unix</span> operating systems the
<tt class="module">posix</tt> module is not available, but a subset is always
available through the <tt class="module"><a href="module-os.html">os</a></tt> interface.  Once <tt class="module"><a href="module-os.html">os</a></tt> is
imported, there is <em>no</em> performance penalty in using it instead
of <tt class="module">posix</tt>.  In addition, <tt class="module"><a href="module-os.html">os</a></tt><a id='l2h-2969' xml:id='l2h-2969'></a>
provides some additional functionality, such as automatically calling
<tt class="function">putenv()</tt> when an entry in <code>os.environ</code> is changed.

<P>
The descriptions below are very terse; refer to the corresponding
<span class="Unix">Unix</span> manual (or POSIX documentation) entry for more information.
Arguments called <var>path</var> refer to a pathname given as a string.

<P>
Errors are reported as exceptions; the usual exceptions are given for
type errors, while errors reported by the system calls raise
<tt class="exception">error</tt> (a synonym for the standard exception
<tt class="exception">OSError</tt>), described below.

<P>

<p><br /></p><hr class='online-navigation' />
<div class='online-navigation'>
<!--Table of Child-Links-->
<A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></a>

<UL CLASS="ChildLinks">
<LI><A href="posix-large-files.html">8.1.1 Large File Support</a>
<LI><A href="posix-contents.html">8.1.2 Module Contents</a>
</ul>
<!--End of Table of Child-Links-->
</div>

<DIV CLASS="navigation">
<div class='online-navigation'>
<p></p><hr />
<table align="center" width="100%" cellpadding="0" cellspacing="2">
<tr>
<td class='online-navigation'><a rel="prev" title="8. Unix Specific Services"
  href="unix.html"><img src='../icons/previous.png'
  border='0' height='32'  alt='Previous Page' width='32' /></A></td>
<td class='online-navigation'><a rel="parent" title="8. Unix Specific Services"
  href="unix.html"><img src='../icons/up.png'
  border='0' height='32'  alt='Up One Level' width='32' /></A></td>
<td class='online-navigation'><a rel="next" title="8.1.1 Large File Support"
  href="posix-large-files.html"><img src='../icons/next.png'
  border='0' height='32'  alt='Next Page' width='32' /></A></td>
<td align="center" width="100%">Python Library Reference</td>
<td class='online-navigation'><a rel="contents" title="Table of Contents"
  href="contents.html"><img src='../icons/contents.png'
  border='0' height='32'  alt='Contents' width='32' /></A></td>
<td class='online-navigation'><a href="modindex.html" title="Module Index"><img src='../icons/modules.png'
  border='0' height='32'  alt='Module Index' width='32' /></a></td>
<td class='online-navigation'><a rel="index" title="Index"
  href="genindex.html"><img src='../icons/index.png'
  border='0' height='32'  alt='Index' width='32' /></A></td>
</tr></table>
<div class='online-navigation'>
<b class="navlabel">Previous:</b>
<a class="sectref" rel="prev" href="unix.html">8. Unix Specific Services</A>
<b class="navlabel">Up:</b>
<a class="sectref" rel="parent" href="unix.html">8. Unix Specific Services</A>
<b class="navlabel">Next:</b>
<a class="sectref" rel="next" href="posix-large-files.html">8.1.1 Large File Support</A>
</div>
</div>
<hr />
<span class="release-info">Release 2.4.2, documentation updated on 28 September 2005.</span>
</DIV>
<!--End of Navigation Panel-->
<ADDRESS>
See <i><a href="about.html">About this document...</a></i> for information on suggesting changes.
</ADDRESS>
</BODY>
</HTML>