@Kevin King
guide_ndx still only allows one file to be checked at a time.
If you want to find out if a file is a UniData file and how many indicies it has without UniData running, there is an undocumented enginnering command you can use (this is not something that is new to UniData 8). You need an understanding of the information that the tool returns and would need to do some scripting around the command to ensure the file is a UniData file, as the tool in questions may still report the file is a UniData file when it's not, so you need to be careful on examing the results in that regard and checking.
The command in question is fileview and if used to view the primary group of a file, it will allow to see (and modify) various header elements of the file. The counter returned in the idxinf field denotes the number of indicies a file has.
ORDERS has two indices
fileview -p1 ORDERS
File Name --------> ORDERS (static, non-RFS, 64-bit)
modulo --------------> 31
hashtype ------------> 0x0, Hash Function: 0
HashVersion ---------> 1.0
version -------------> 2
blksiz --------------> 0 (1024)
idxinf --------------> 2
bproof --------------> 0
file operation ------> 0
PropertyOffset ------> 0 (0x0)
mul_of --------------> 0
rm ------------------> 255
prt_at --------------> 192
nullv --------------> 129
file size -----------> 33792 (33 blocks)
VOC has none
fileview -p1 VOC
File Name --------> VOC (static, non-RFS, 32-bit)
modulo --------------> 101
hashtype ------------> 0x3, Hash Function: 3
HashVersion ---------> 1.0
version -------------> 2
blksiz --------------> 0 (1024)
idxinf --------------> 0
bproof --------------> 0
file operation ------> 0
PropertyOffset ------> 0 (0x0)
mul_of --------------> 0
rm ------------------> 255
prt_at --------------> 192
nullv --------------> 129
file size -----------> 118784 (116 blocks)
Now in terms of working out if something is a UniData file , do not rely on the fileview output of 'File Name --------> ORDERS (static, non-RFS, 64-bit)' alone. You need to do more checking on the output provided and understand what the range of some of the header values are supposed to be. Sadly we do not have any formal documentation on fileview as it is intended as an engineering only interface.
This should at least give you some assistance into finding the information you are looking for.