sudo apt-get install libhidapi-dev
git clone https://github.com/rgerganov/footswitch.git
cd footswitch
make
sudo make install

brew tap rgerganov/footswitch https://github.com/rgerganov/footswitch.git
brew install --HEAD footswitch

footswitch [-123] [-r] [-s <string>] [-S <raw_string>] [-ak <key>] [-m <modifier>] [-b <button>] [-xyw <XYW>]
   -r          - read all pedals
   -1          - program the first pedal
   -2          - program the second pedal (default)
   -3          - program the third pedal
   -s string   - append the specified string
   -S rstring  - append the specified raw string (hex numbers delimited with spaces)
   -a key      - append the specified key
   -k key      - write the specified key
   -m modifier - ctrl|shift|alt|win
   -b button   - mouse_left|mouse_middle|mouse_right
   -x X        - move the mouse cursor horizontally by X pixels
   -y Y        - move the mouse cursor vertically by Y pixels
   -w W        - move the mouse wheel by W

You cannot mix -sSa options with -kmbxyw options for one and the same pedal

scythe [-123] [-r] [-a <key>] [-m <modifier>] [-b <button>]
   -r          - read all pedals
   -1          - program the first pedal
   -2          - program the second pedal (default)
   -3          - program the third pedal
   -a key      - append the specified key
   -m modifier - ctrl|shift|alt|win
   -b button   - mouse_left|mouse_double|mouse_right

You cannot mix -a and -m options with -b option for one and the same pedal

footswitch -r
    read the persisted function in each pedal and print it on the console
footswitch -k a
    program the second pedal to print the letter 'a' (also work for single pedal devices);
    as a general rule you don't need to specify -1, -2 or -3 if you have only one pedal
footswitch -1 -k a -2 -k b -3 -k c
    program the first pedal to print 'a', second pedal to print 'b' and third pedal to print 'c'
footswitch -1 -k esc -2 -k enter
    program the first pedal as Escape key and the second pedal as Enter key
footswitch -1 -m ctrl -k a -3 -m alt -k f4
    program the first pedal as Ctrl+a and the third pedal as Alt+F4
footswitch -1 -m ctrl -k a -3 -m shift -m alt -k s
    program the first pedal as Ctrl+a and the third pedal as Shift+Alt+s (Wikipedia "save")
footswitch -m ctrl -b mouse_middle
    program the second pedal as Ctrl+<middle_mouse_click>
footswitch -s 'hello world'
    program the second pedal to print 'hello world'
footswitch -s 'hello' -s ' ' -s 'world'
    this will also program the second pedal to print 'hello world';
    you can specify multiple -s options and each option will append to the resulting string
footswitch -a esc -a i
    program the second pedal to produce Escape and then the letter 'i'
footswitch -s ls -a enter
    program the second pedal to print 'ls' and then hit Enter
footswitch -S '29 C'
    program the second pedal with the specified 'raw' string (hex numbers delimited with spaces);
    you can find the hex code for each key at http://www.freebsddiary.org/APC/usb_hid_usages.php
footswitch -1 -x 10 -2 -w 15 -3 -y -10
    program first pedal to move the mouse cursor 10 pixels left;
    second pedal to move mouse wheel 15 units up;
    third pedal to move the mouse cursor 10 pixels right

scythe -r
    read the persisted function in each pedal and print it on the console
scythe -1 -a a -2 -a b -3 -a c
    program the first pedal to print 'a', second pedal to print 'b' and third pedal to print 'c'
scythe -1 -m ctrl -a h -a o -2 -m alt -a f4 -3 -b mouse_double
    program the first pedal as Ctrl+h+o, the second pedal as Alt+F4 and the third pedal as double click