What does %~dp0 or %~d0 mean?
The magic variables %n contains the arguments used to invoke the file: %0 is the path to the bat-file itself, %1 is the first argument after, %2 is the second and so on.
Since the arguments are often file paths, there is some additional syntax to extract parts of the path. ~d is drive, ~p is the path (without drive), ~n is the file name. They can be combined so ~dp is drive+path.
%~dp0 is therefore pretty useful in a bat: it is the folder in which the executing bat file resides.
The path (without drive) where the script is : %~p0
The drive where the script is : %~d0
You can also get other kinds of meta info about the file: ~t is the timestamp, ~z is the size.
Look here for a reference for all command line commands. The tilde-magic codes are described under for.
%~1 - expands %1 removing any surrounding quotes (")
%~f1 - expands %1 to a fully qualified path name
%~d1 - expands %1 to a drive letter only
%~p1 - expands %1 to a path only
%~n1 - expands %1 to a file name only
%~x1 - expands %1 to a file extension only
%~s1 - expanded path contains short names only
%~a1 - expands %1 to file attributes
%~t1 - expands %1 to date/time of file
%~z1 - expands %1 to size of file
%~$PATH:1 - searches the directories listed in the PATH
environment variable and expands %1 to the fully
qualified name of the first one found. If the
environment variable name is not defined or the
file is not found by the search, then this
modifier expands to the empty string
%~dp1 - expands %1 to a drive letter and path only
%~nx1 - expands %1 to a file name and extension only
%~dp$PATH:1 - searches the directories listed in the PATH
environment variable for %1 and expands to the
drive letter and path of the first one found.
%~ftza1 - expands %1 to a DIR like output line