Batch/DOS --Update Anitvirus

update_antivirus.bat

//Update Anti Virus

Home users just want to update their antivirus. Business users 
are usually admins who want to grab the latest update so they can 
redistribute it within their company. And they want to know when 
a new update is available so they can trigger some other 
notification or distribution program. The problem is that the name 
of the update changes, so that makes it harder to code for something 
when you don't know the name in advance!

Okay. So here's the trick. No scripting or external programs needed. 
You can do it all in batch. The batch will control the command-line 
FTP program that is part of Windows. You don't NEED know the name. 
Instead you just do an FTP DIR (or LS) command to show all sdat files. 
And you use the FTP MGET command to grab the files regardless of name.
The FTP sequence is like this:

open ftp.nai.com
anonymous
naiuser@nai.com
dir virusdefs/4.x/sdat* C:\today.txt
bye


Having done that, you'll have a C:\today.txt file with the following 
text:

06-01-04 06:08PM 5518927 sdat4364.exe

Yesterday, you did the same thing. Think...... You can compare 
yesterday's file with today's file! If there is no update, the files 
will be the same. You use the FC command to compare files:

fc C:\yesterday.txt C:\today.txt | find "no differences encountered"
if errorlevel 1 goto NEWFILE
goto OLDSTUFF

So -- Do I put it all together for you? Let's call the FTP text above 
"today.scr". We'll make a separate FTP download script called "sdat.scr" 
which will have this:

open ftp.nai.com
anonymous
naiuser@nai.com
cd /virusdefs/4.x
lcd C:\
binary
hash
prompt
mget sdat*.exe
bye

And the batch file that ties them all together:

copy /y C:\today.txt C:\yesterday.txt
%windir%\system32\ftp.exe -s:C:\today.scr
fc C:\yesterday.txt C:\today.txt | find "no differences encountered"
if not errorlevel 1 goto DONE
C:
cd C:\
for %%x in (sdat*.exe) do del %%x
%windir%\system32\ftp.exe -s:C:\sdat.scr
:: Insert notification and distribution commands here
NET SEND Administrator There is a Virus Update
for %%x in (sdat*.exe) do copy /y %%x F:\Share\sdat.exe
:DONE

I used the first FOR line to delete the old SDAT file. It's really 
just another way of doing a "del sdat*.exe". Doing it with FOR avoids 
some problems with "Are you sure" prompts with wildcard deletes, but... 
I don't think it's really needed. If "del sdat*.exe" works for you, 
you could use it. The second FOR command copies the sdat file over to 
your network with a common name. The common name makes it easy for you 
to hard-code an update script for your clients. Once again, using FOR 
avoids problems with wildcard copies. I'm willing to bet the simpler 
"copy sdat*.exe F:\Share\sdat.exe" wouldn't work reliably on all systems, 
but you could try it if you don't like the FOR command. You can see I 
have an aversion to wildcard "action" commands and prefer to limit wildcards 
to generating virtual lists.

I could have written a single larger batch file that created the two needed 
FTP scripts as needed, but keeping them separate makes it easier to 
understand. Oh -- Be sure to create a dummy empty "today.txt" before you run 
the batch file the first time. That way the COPY and FC commands won't be 
upset on the first run!