file size different from ls to du

[Bogdan TARU]

	Hi everyone,

 I have sort of a newbie question, but that I cannot explain myself. I get
some large files in 'ls -al', but when I 'measure' them with 'du', the
size is much small. Example:

(17:13) bgd@(bgd)[~/temp] ls -alsh my_file
19120 -rw-r--r--  1 root  bgd  763M Jul 29 16:56 my_file
(17:13) bgd@(bgd)[~/temp] du -sh my_file
 19M    my_file

 So the 'ls -alsh' shows a file in size of 763M, but 19M of sectors are
really 'occupied'. Can someone explain, please?

 Thanks,
 bogdan