Creating a memory mapped file

[KDan]

Hi everyone!!

First of all am quite new to cpp especially under linux.

I am currently working on a small project under Linux and am having to deal with large number of data(larger than 1 GB). numerous number of operation is to be done with these data. for example: sorting, searching, comparing ... etc. so in order to perform all these operations it is important that these data are in the memory...

in order to deal with such a large amount of data am thinking of using a memory mapped file..
can anyone help me or guide me in the steps of creating a memory mapped file?

Please help ..
Thanking in advance

[vijayan121]

> man mmap <Enter>
at the command prompt on your system. it should give you all the information that you require.you would see something like this: http://www.freebsd.org/cgi/man.cgi?query=mmap&apropos=0&sektion=0&manpath=FreeBSD+7.0-stable&format=html

[james_zheng]

hi KDan !
the following steps tell u how to create a memory mapped file:
1. use 'open' function to get a file description;
2. create a memory maped file using 'mmap' function, which returns a pointer to the address of the memory;
3. 'munmap' function close a memory maped file;
4. 'close' to close the file;
btw:why not use database operation instead?