is this an informix database?

I have a set of files with .rpt and .ixc extensions. Can anyone tell me if this is informix - if not, what type of db it is? More info: The data inside the files is not ASCII readable (perhaps is binary or encrypted?) The ixc file appears to be some type of index file with possible offsets into the .rpt file? I have an additional .rpt file which looks like a report output file - this is ascii readable. There is also an inf file that contains the following lines: line 1: date line 2: date line 3: BID.332 line 4: CUST.332 line 5: date line 6:18SHUTDOWNTIME Any help is appreciated! Thanks, Karen Peterson