Tonight I've been studying MAME 0.78u1 listinfo output in an attempt to improve my understanding of some aspects of MAME.

Just for fun I put together a few programs to generate some lists - biossets, baddumps and nodumps. I used some old school awk and grep to obtain the lists. I don't understand why my counts differ so wildly from those produced in the status statistics output in ClrMamePro - I know Roman says not to trust the statistics output but I'm surprised how different it is from my own calculations. Details follow.

Firstly, here is the output from
ClrMamePro's statistics window after a scan:
Missing Sets: 0 of 4718
Wrong Spelled Sets: 0 [0 fixed]
Wrong Named Sets: 0 [0 fixed]

Missing Roms: 0 of 68259
Wrong Named Roms: 0 [0 fixed]
Wrong Spelled Roms: 0 [0 fixed]
Wrong Sized Roms: 0 [0 fixed]
Wrong CRC32s: 0
Wrong MD5s:
Wrong SHA1s:

Missing Samples: 0 of 2074
Wrong Spelled Samples: 0 [0 fixed]

Missing DiskImages: 0 of 30
Wrong Spelled DiskImages: 0 [0 fixed]
Wrong Named DiskImages: 0 [0 fixed]
Wrong CHD_MD5/SHA1s: 0

Unneeded Files/Folders: 0 [0 fixed]

Number Of Sets: 4718
Number Of Parents: 1045
Number Of Clones: 2047
Number Of Others: 1626
Number Of Roms: 68259
Number Of Samples: 2074
Number Of 'nodump' ROMs: 146
Number Of 'baddump' ROMs: 156

Secondly, A clean "mame -listinfo > listinfo.txt" run against mame078u1 with no history.dat/mameinfo.dat in the path produces a file of size with following signature according to ClrMamePro's About box:

Path: C:\tim\emulators\mame\mame78u1\
Name: listinfo.txt
Size: 15574139
CRC32: 733c6c48
~CRC32: 8cc393b7
MD5: 69677777e6141d1aa74dd21c27cc79af
SHA1: 74568ee3d184a41f067eb5bc27f15e60eca35112

Thirdly, the following results are obtained for lines with "baddump" or "nodump" in them:
"grep baddump listinfo.txt | wc -l" produces 127 lines
"grep nodump listinfo.txt | wc -l" produces 175 lines

Fourthly, the following are obtained for lines with "baddump" or "nodump" in them but not "merge":
"grep baddump listinfo.txt | grep -v merge | wc -l" produces 96 lines
"grep nodump listinfo.txt | grep -v merge | wc -l" produces 175 lines

Here are the details (obtained from awk):
http://members.iinet.net.au/~tmorrow/emulation/baddump.txt
http://members.iinet.net.au/~tmorrow/emulation/nodump.txt

Why the huge discrepancy of 96 vs 156 baddumps and 175 vs 146 nodumps?

Cheers,
Tim