Mac Serial ERROR 9

General
1

Trying to connect an FTDI USB-Serial adapter to a Macbook 11,1 running Catalina, we’re getting the following error code:

ERROR 9

Can anyone please tell me what this error code means? It’s not in the Xojo manual, and https://osstatus.com doesn’t help. Thanks.

2

from MacErrors.h:

dsLineAErr = 9, /line 1010 trap error/

errno.h:

#define EBADF 9 /* Bad file descriptor */

So maybe a the second?