1create_datafile_index(3)        Allegro manual        create_datafile_index(3)
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NAME

6       create_datafile_index  -  Creates an index for a datafile. Allegro game
7       programming library.
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SYNOPSIS

10       #include <allegro.h>
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13       DATAFILE_INDEX *create_datafile_index(const char *filename);
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DESCRIPTION

16       Creates an index for a datafile, to speed up loading single objects out
17       of it. This is mostly useful for big datafiles, which you don't want to
18       load as a whole. The index will store the offset of all objects  inside
19       the    datafile,    and   then   you   can   load   it   quickly   with
20       "load_datafile_object_indexed" later.   Use  destroy_datafile_index  to
21       free the memory used by it again.
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23       Note:  If the datafile uses global compression, there is no performance
24       gain from using an index, because seeking to the offset still  requires
25       to uncompress the whole datafile up to that offset.  Example:
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27          DATAFILE_INDEX *index = create_datafile_index("huge.dat");
28          DATAFILE *object = load_datafile_object_indexed(index, 1234);
29          ...
30          unload_datafile_object(object);
31          destroy_datafile_index(index);
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RETURN VALUE

34       A pointer value which you can pass to load_datafile_object_indexed.
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SEE ALSO

38       destroy_datafile_index(3), load_datafile_object_indexed(3)
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42Allegro                          version 4.4.3        create_datafile_index(3)
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