The following two methods are equivalent:

    perl -lpe 'substr $_, 0, 9, ""' file

    perl -lpe '$_ = substr $_, 9'   file
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If you want to edit the file in-place you can add the -i switch:

    # Edited in-place
    perl -i     -lpe 'substr $_, 0, 9, ""' file

    # Edited in-place with back-up
    perl -i.bak -lpe 'substr $_, 0, 9, ""' file
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