Linux and Unix fc command tutorial with examples

Tutorial on using fc, a UNIX and Linux command for editing and re-executing commands previously entered into an interactive shell. Examples of editing and re-executing the last command, editing and executing a previous command, setting the text editor to be used, listing previous commands and executing a command without editing it.

September 28, 2016
Updated September 19, 2024

What is the fc command? ¶

The fc command is a command line utility for listing, editing and re-executing commands previously entered into an interactive shell. The fc command is a shell builtin meaning the command comes from the shell rather than the operating system. As such fc can vary slightly depending on the shell being used. The fc command is present is most shells including bash, zsh and ksh. The fc command can be very useful for editing long commands entered into a shell and re-executing them without having to rewrite the entire command. The examples here are from the zsh shell.

How to edit and re-executing the last command ¶

To edit and run the last command entered into a shell run the fc command. This will open a text editor and allow the command to be edited. When the file is saved the command will be run. This can be very useful for editing and re-executing complicated commands in a shell.

echo 'last command'
    last command
    fc
    ...file edited, string changed to 'hello'..
    echo 'hello'
    hello

The text editor invoked by fc can be specified firstly in the FCEDIT environment variable. In the following example the FCEDIT environment variable is set to nano. When the fc command is run the nano text editor will be invoked. If FCEDIT is not set the EDITOR environment variable will be used. After that the vi command will be used.

export FCEDIT=nano
    ls
    fc

How to list previous commands ¶

To list previous commands and not execute them pass the -l option. This will show a list of commands run in the current interactive shell.

fc -l
    700  ip link set dev wlp3s0 down
    701  sudo ip link set dev wlp3s0 down
    702  ip a
    703  dmesg
    ...

To start from a specific command pass the number to fc along with the -l option.

fc -l 600
    600  cat /etc/modules-load.d/bcwc-pcie.conf
    601  sudo reboot
    602  startx
    ...

To list a specific range of commands the first and last numbers may also be passed.

fc -l 701 702
    701  sudo ip link set dev wlp3s0 down
    702  ip a

To suppress numbers in listings the -n can be used.

fc -ln 701 702
    sudo ip link set dev wlp3s0 down
    ip a

How to edit and re-execute a previous command ¶

To edit and re-execute a previous command first find the command to edit using fc -l. Then pass the number to be edited and re-executed.

fc -l
    841 echo 'hello'
    842 echo 'world'
    fc 841
    echo 'hello'
    hello

How to set the text editor dynamically ¶

To set the text editor that is used to edit commands dynamically pass the editor to be used to the -e option. In the following example the pwd command will be edited in vi.

pwd
    fc -e vi

On saving the file the command will be run.

How to view when commands were run ¶

For the zsh shell it is possible to see when commands were run by passing the -d option to show the timestamp for each command. In the following example the -l options is also passed to only list commands.

fc -ld
    700  14:43  ip link set dev wlp3s0 down
    701  14:43  sudo ip link set dev wlp3s0 down
    702  14:43  ip a

A full timestamp may be shown with the -f option.

fc -lf
    700  9/28/2016 14:43  ip link set dev wlp3s0 down
    701  9/28/2016 14:43  sudo ip link set dev wlp3s0 down
    702  9/28/2016 14:43  ip a

For a European date format the -E option may be used.

    fc -lE
    fc -lE 700 702
    700  28.9.2016 14:43  ip link set dev wlp3s0 down
    701  28.9.2016 14:43  sudo ip link set dev wlp3s0 down
    702  28.9.2016 14:43  ip a

How to re-execute a command without editing it ¶

To re-execute a command without invoking an editor pass the -e option with a dash. This will cause the command to be run immediately.

echo 'hello'
    hello
    fc -e -
    echo 'hello'
    hello

This can also accept a command number or a range of numbers from the history.

fc -l
    842  echo 'hello world'
    843  fc -e -
    844  echo 'hello'
    fc -e - 842
    echo 'hello world'
    hello