I'm not certain a batch file can do that. I know how to get VBA to do it. I know how to get T-SQL to do it. I've done a lot of tasks with batch files, but I'm not sure what you're asking can be done.
I took a look through the XP command shell documentation at:
http://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/ntcmds_o.mspx?mfr=true
I didn't see anything that would do what you're looking for. I didn't look all that thoroughly, so I may have overlooked something. Take a look at the command references on that page and see if you can find something.
I think it would be easier, however, to set up a script to do it, rather than trying to use a command prompt batch file. Since it can be done in VBA, you might try doing it through the Word VBA editor (create a macro). The OpenTextFile method of the FileSystem object is the one to use, if you use that solution.
If you have an IDE for a real programming language and can build a stand-alone application, use whatever objects/methods that language uses. If not, but you do have Word/Excel/Access, you can build a macro for it. Not as convenient as a .bat file, but it will work.
Or perhaps someone else will be able to suggest a means of doing it through a batch file.
