12-08-2015, 01:49 AM
I had the same or similar problem with the Windows version of that command a few months back - can't remember the details exactly but the "fix" is to use the Linux version instead, i.e. :
$ cat single_hccaps/*.hccap > all_in_one/multi.hccap
$ cat single_hccaps/*.hccap > all_in_one/multi.hccap