Memory mapped files in C

Question

I played with memory mapped files in C and wondered if there is a way to replace FILE * from fopen with a transparent memory file.

Example:

FILE * fp = g_fopen(...);

//Program does things to this fp.

fclose();

But instead, is it possible to have FILE * fp = my_fopen (...)

Where my own function will open the file on the mmap disk, it may change the contents and then pass FILE * without the program, seeing anything other than the new my_fopen () and my_fclose ().

Is it possible to do this without having to rewrite the method of performing operations in the program?

Answer 1

- " ". : http://developers.sun.com/solaris/articles/lib_interposers.html

---

Oracle , , , / - Oracle.

, :

• , 2001 : Interposers for Fun and Profit (Dr. Dobbs)
• developers.sun.com , , 2001 ; repost: (Wayback Machine)
• Sun Studio/Oracle Solaris Studio. .

Answer 2

IO , VM/buffer . , , ? , ?

Answer 3

. / , , my_fopen

FILE * my_fopen()
{
    FILE * myfp
    myfp = fopen(...);
    mmap(fileno(myfp),...);
    return myfp;
}