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<H2><A NAME="SECTION0010110000000000000000"></A><A NAME="posix-large-files"></A>
<BR>
8.1.1 Large File Support 
</H2>

<a id='l2h-2970' xml:id='l2h-2970'></a>

<P>
Several operating systems (including AIX, HPUX, Irix and Solaris)
provide support for files that are larger than 2 Gb from a C
programming model where <tt class="ctype">int</tt> and <tt class="ctype">long</tt> are 32-bit
values. This is typically accomplished by defining the relevant size
and offset types as 64-bit values. Such files are sometimes referred
to as <i class="dfn">large files</i>.

<P>
Large file support is enabled in Python when the size of an
<tt class="ctype">off_t</tt> is larger than a <tt class="ctype">long</tt> and the <tt class="ctype">long long</tt>
type is available and is at least as large as an <tt class="ctype">off_t</tt>. Python
longs are then used to represent file sizes, offsets and other values
that can exceed the range of a Python int. It may be necessary to
configure and compile Python with certain compiler flags to enable
this mode. For example, it is enabled by default with recent versions
of Irix, but with Solaris 2.6 and 2.7 you need to do something like:

<P>
<div class="verbatim"><pre>
CFLAGS="`getconf LFS_CFLAGS`" OPT="-g -O2 $CFLAGS" \
        ./configure
</pre></div> 
<P>
On large-file-capable Linux systems, this might work:

<P>
<div class="verbatim"><pre>
CFLAGS='-D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64' OPT="-g -O2 $CFLAGS" \
        ./configure
</pre></div> 
<P>

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	55	<H2><A NAME="SECTION0010110000000000000000"></A><A NAME="posix-large-files"></A>
	56	<BR>
	57	8.1.1 Large File Support
	58	</H2>
	59
	60	<a id='l2h-2970' xml:id='l2h-2970'></a>
	61
	62	<P>
	63	Several operating systems (including AIX, HPUX, Irix and Solaris)
	64	provide support for files that are larger than 2 Gb from a C
65	programming model where <tt class="ctype">int</tt> and <tt class="ctype">long</tt> are 32-bit
66	values. This is typically accomplished by defining the relevant size
67	and offset types as 64-bit values. Such files are sometimes referred
68	to as <i class="dfn">large files</i>.
69
70	<P>
71	Large file support is enabled in Python when the size of an
72	<tt class="ctype">off_t</tt> is larger than a <tt class="ctype">long</tt> and the <tt class="ctype">long long</tt>
73	type is available and is at least as large as an <tt class="ctype">off_t</tt>. Python
74	longs are then used to represent file sizes, offsets and other values
75	that can exceed the range of a Python int. It may be necessary to
76	configure and compile Python with certain compiler flags to enable
77	this mode. For example, it is enabled by default with recent versions
78	of Irix, but with Solaris 2.6 and 2.7 you need to do something like:
79
80	<P>
81	<div class="verbatim"><pre>
82	CFLAGS="`getconf LFS_CFLAGS`" OPT="-g -O2 $CFLAGS" \
83	./configure
84	</pre></div>
85	<P>
86	On large-file-capable Linux systems, this might work:
87
88	<P>
89	<div class="verbatim"><pre>
90	CFLAGS='-D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64' OPT="-g -O2 $CFLAGS" \
91	./configure
92	</pre></div>
93	<P>
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