pass stdout as file name for command line util?

Solution 1: Using process substitution

The most convenient way of doing this is by using process substitution. In bash the syntax looks as follows:

foo -o >(other_command)

(Note that this is a bashism. There’s similar solutions for other shells, but bottom line is that it’s not portable.)

Solution 2: Using named pipes explicitly

You can do the above explicitly / manually as follows:

1. Create a named pipe using the mkfifo command.

   mkfifo my_buf
   

2. Launch your other command with that file as input

   other_command < my_buf
   

3. Execute foo and let it write it’s output to my_buf

   foo -o my_buf
   

Solution 3: Using /dev/stdout

You can also use the device file /dev/stdout as follows

foo -o /dev/stdout | other_command