A handy trick in Bash is to split a stream to process it in more than one way without saving a temporary copy:
# Make 3 a copy of 1 (stdout) exec 3>&1 result="$(command to generate stream \ | tee /dev/fd/3 \ | command to process stream)" # Now work with $result # The original stream also went to the console
The actual case I worked with this morning was a very simple demonstration:
#!/bin/bash exec 3>&1 echo -e "Bob is my friend.\nFred is my friend, too." \ | tee /dev/fd/3 \ | cut -f1 -d' ' >&2
Which simply prints:
Bob is my friend. Fred is my friend.
stdout and to
stderr it prints: