Need efficient way to read file in reverse

[Chuck Ocheret]

I recommend that you check to see if your system supports some form of
memory mapping of a file.  On some systems there is the mmap(2) call on
others a version of shmat(2) allows you to do mostly the same thing.
Not all systems provide such a mechanism.  When you map a file in using
either of these you get a pointer to memory which maps directly to a
specified file on the file system (can also be a device).  This gives
you full random access to all bytes in the file.  Read it backwards,
forwards, or however you wish; your file has just become a char *.

~chuck
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+--------------------+   Chuck Ocheret, Sr. Staff Engineer   +---------------+
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