cvs update -Ad

工作中经常用到的指令，一直不知道-Ad的含义，现在把所有是选项都列出来，方便查阅

Usage: cvs update [-APCdflRp] [-k kopt] [-r rev] [-D date] [-j rev]
    [-I ign] [-W spec] [files...]
        -A      Reset any sticky tags/date/kopts.
        -P      Prune empty directories.
        -C      Overwrite locally modified files with clean repository copies.
        -d      Build directories, like checkout does.
        -f      Force a head revision match if tag/date not found.
        -l      Local directory only, no recursion.
        -R      Process directories recursively.
        -p      Send updates to standard output (avoids stickiness).
        -k kopt Use RCS kopt -k option on checkout. (is sticky)
        -r rev  Update using specified revision/tag (is sticky).
        -D date Set date to update from (is sticky).
        -j rev  Merge in changes made between current revision and rev.
        -I ign  More files to ignore (! to reset).
        -W spec Wrappers specification line.