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<P><FONT SIZE=2 FACE="Arial">Hi,</FONT>
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<P><FONT SIZE=2 FACE="Arial">I'm using the c function "mmap" to memory map binary files into an int**. (on a 32 bit machine).</FONT>
<BR><FONT SIZE=2 FACE="Arial">There are a total of 22 files - the maximum of which is about 450MB. Since 4 bytes per int, this will imply 112M addresses will be needed.</FONT></P>
<P><FONT SIZE=2 FACE="Arial">So:</FONT>
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<P><FONT SIZE=2 FACE="Arial">array[0] = file1</FONT>
<BR><FONT SIZE=2 FACE="Arial">array[1] = file2</FONT>
<BR><FONT SIZE=2 FACE="Arial">array[21] = file22</FONT>
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<P><FONT SIZE=2 FACE="Arial">In total, these 22 files come to about 3.4GB - roughly 850M addresses.</FONT>
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<P><FONT SIZE=2 FACE="Arial">However, the function crashes and gives out the message ENOMEM after mapping about 2.6GB.</FONT>
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<P><FONT SIZE=2 FACE="Arial">Does anyone know what's going wrong??? None of it makes sense to me because:</FONT>
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<P><FONT SIZE=2 FACE="Arial">(a) if problem was that 2^31 max addresses, then would crash surely after mapping 2^31bytes (less than 2.6)</FONT>
<BR><FONT SIZE=2 FACE="Arial">(b) problem doesn't seem to be lack of swap space.</FONT>
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<P><FONT SIZE=2 FACE="Arial">Is there a maximum memory limit in mapping?</FONT>
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<P><B><FONT SIZE=2 FACE="Arial">Nigel Rochford</FONT></B>
<BR><FONT SIZE=2 FACE="Arial">Analyst Programmer</FONT>
<BR><FONT SIZE=2 FACE="Arial">+44 306 3563</FONT>
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