I tried to use the command:
but the message I got was
Couldn't get a file descriptor referring to the console
What can I do?
Were you literally typing in the “<“ and “>” characters in that command, or did you mean:
Where FILENAME is a place holder variable for potentially any file name?
The redirection characters of < > have special meaning to and get interpreted by the shell and their use as you described might well cause that error message as your command in that case means something akin to ‘make the standard input file descriptor for the open command to be filename.pdf and make its standard output file descriptor to be UNNAMED FILE’
That probably accounts for your error.
open /Users/yourid/subfolder1/subfolder2/your filename.pdf
This will work because
Preview is the default handler for PDF files. If there is no default handler, OR you wish to open with a different app, use the
-a option, and spec the handler/app you want to use. And read
man open... or just type
open on the command line by itself.