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Output Handling

fzf outputs the selected line(s) to standard output. How you capture and use that output determines the power of fzf in your workflows.

Single Selection​

# Basic capture
selected=$(ls | fzf)
echo "You chose: $selected"

# Use directly in a command (command substitution)
nvim $(find . -type f -name "*.lua" | fzf)
cat $(ls /etc | fzf)
ssh $(grep -E "^Host " ~/.ssh/config | awk '{print $2}' | fzf)
warning

If the selection contains spaces, always use quotes: nvim "$(find . | fzf)". The --print0 / --read0 flags handle filenames with newlines (rare but possible).

Multi-select Output (--multi)​

With -m, each selected item is printed on its own line:

# Select multiple files, open all in vim
vim $(find . -type f | fzf -m)

# Select multiple, delete interactively
find . -name "*.bak" | fzf -m | while read -r file; do
  rm -v "$file"
done

# Pipe multi-select output into xargs
find . -name "*.log" | fzf -m | xargs grep "ERROR"

Handling Spaces in Filenames​

Option 1: Quote substitution

while IFS= read -r file; do
  nvim "$file"
done < <(find . | fzf -m)

Option 2: Null-delimited

find . -print0 | fzf --read0 --print0 | xargs -0 cat

The --expect Flag — Capture Which Key Was Pressed​

--expect lets you define alternative action keys. fzf then outputs the pressed key as the first line, your selection as the second:

# Define ctrl-v and ctrl-x as alternate keys
result=$(ls | fzf --expect=ctrl-v,ctrl-x)
key=$(head -1 <<< "$result")
file=$(tail -1 <<< "$result")

case "$key" in
  ctrl-v) nvim "$file" ;;          # open in vim
  ctrl-x) xdg-open "$file" ;;     # open with GUI app
  *)      cat "$file" ;;           # default: print to terminal
done

This pattern lets a single fzf invocation trigger different actions.

--bind with execute vs become​

Rather than capturing output and acting on it in the shell, you can trigger actions directly inside fzf using --bind:

# execute: run a command without leaving fzf
ls | fzf --bind "enter:execute(nvim {})"

# become: replace fzf process with the command (cleaner terminal)
ls | fzf --bind "enter:become(nvim {})"

# ctrl-v: open in vertical split (neovim server)
ls | fzf --bind "ctrl-v:execute(nvim -o {} &)"

The {} placeholder is replaced with the currently highlighted item.

--with-nth — Display Subset of Fields​

Use --with-nth to show only some columns in fzf's list (while preserving the full line for output):

# ps aux has many columns — show only columns 1 and 11 (user and command)
ps aux | fzf --header-lines=1 --with-nth=1,11

# Show only column 2 (PID)
ps aux | fzf --with-nth=2

--nth — Search Only Specific Fields​

Limit which fields fzf fuzzy-matches against:

# Only search column 2 (PID) in ps output
ps aux | fzf --nth=2

# Only search columns 2 and 3 (leave user column unsearchable)
ps aux | fzf --nth=2,3

Using --delimiter​

Change the field separator for --nth and --with-nth:

# Colon-separated: search only field 1 (before first colon)
cat /etc/passwd | fzf -d: --nth=1

# Tab-separated
cat data.tsv | fzf -d$'\t' --with-nth=1,3

Output with Context: --print-query​

Print the query string as the first line of output (before the selection):

result=$(ls | fzf --print-query)
query=$(head -1 <<< "$result")
selection=$(tail -1 <<< "$result")
echo "Query: $query → Selected: $selection"

Useful when the query itself is semantically meaningful (e.g., typed a hostname that isn't in the list yet).

What's Next​