[Libreoffice] How to Update the Downloaded Source?

[imacat]

Dear all,

    Hi.  This is imacat from Taiwan.  I followed the instruction in

http://www.libreoffice.org/get-involved/developers/

    to download and compile the source:

% ./autogen.sh --with-git --with-num-cpus=2 --disable-kde4 --disable-opengl
% ./download
% make
% bin/ooinstall

    But how can I update the downloaded source?  Do I need to download
all the 4.4GB source whenever I want to update it?

    And also, how do I know the revision number of the downloaded source?

    Thank you very much in advance.

-- 
Best regards,
imacat ^_*' <imacat at mail.imacat.idv.tw>
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