The "count" key gives you the message number in a given file whereas "countTotal" gives the message number in a set of files. The former gets reset for every input file on the command line but the latter keeps on increasing.
Here is an example:
% grib_count -v file1 file2 1 file1 5 file2 6 total % grib_ls -p count,countTotal,shortName file1 file2 file1 count countTotal shortName 1 1 t 1 of 1 messages in file1 file2 1 2 msl 2 3 tcc 3 4 tcw 4 5 str 5 6 2t 5 of 5 messages in file2 6 of 6 total messages in 2 files
So the count for the 1st message of the 2nd file is 1 (reset) but countTotal is 2.