A. In olden DOS days a utility was available, DOSKEY.EXE, which enabled the user to cycle through previous commands. In NT this is enabled by default and you can cycle through old commands however DOSKEY has other abilities.
To clear the current command line history use command:
You can also optionally tell it how many old commands to keep with the /listsize parameter
doskey /reinstall /listsize=50
would keep 50 old commands.
Its also possible to create macros which allow you to assign a complex command to a single word, for example
doskey dird=dir /ad
Would create a macro dird which only lists directories.
Its also possible to assign a macro to a specific command level application using the /exename switch, for example
doskey /exename=nslookup.exe sets=server 10.129.210.71
Entering sets in NSLOOKUP would now set the server to 10.129.210.71. To view current macros for an image use
C:\> doskey /exename=nslookup.exe /macros