Pattern: Unnecessary echo
Issue: -
The command substitution $(foo) yields the result of command foo with trailing newlines erased, and when it is passed to echo it generally just gives the same result as foo.
Example of incorrect code:
echo "$(cat 1.txt)"
echo `< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c6`Example of correct code:
cat 1.txt # In bash, but faster and still sticks exactly one newline: printf '%s\n' "$(<1.txt)"
# The original `echo` sticks a newline; we want it too.
< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c6; echo