Create custom functions for Fish
03 Jan 2015 linux
Fish has become my favorite shell for the last several months. Most lovely features of it are - auto-complete, auto- capitalization and colorful text. I use fish shell as my default shell with Konsole on my KDE 4.10 desktop.
Creating functions and aliases for bash was easy (adding them to .bashrc or .bash_profile). But fish has a bit different interpretor. It stores
functions as a copy of mostly used and common commands to provide arguments suggestion. Default fish functions are stored at
Well, I don’t want to interfere with their read-only territory. Instead I would create custom functions in my home folder. Configuration path of fish in
my home is
I wanted to use a function that will execute aria2c with my favorite arguments (-x 8 -c link). I also wanted to shorten the name to a 2/3 digit alias. To make it done do the following -
- Choose name of my cherished alias. Make sure that it does not match any other alias or command name.I chose ‘dl’ which is a short form of download.
- Create a file called dl.fish in /home/you/.config/fish/functions
- Open the file in text editor, Kate worked fine for me. Hit nano if you hate GUI.
- Inside that file, paste the following text.
function dl --description "Parallel and resumable download with aria2c" aria2c -c -x 4 $argv end
- The syntax is very simple. Write the function name, add some description and pass arguments of the function in c-style (argv = first argument), not in bash-way ($1 = first argument).
- Save it, and restart fish.
- Now hit any link like the following.
- If you see aria2c is working, be assured that you have created a custom fish function.
you@yourpc ~> dl http://google.com [#1 SIZE:0B/0B CN:1 SPD:0Bs] 2013-03-19 04:40:31.054353 NOTICE - Download complete: /home/you/index.html Download Results: gid|stat|avg speed |path/URI ===+====+===========+=========================================================== 1| OK| 7.3KiB/s|/home/you/index.html Status Legend: (OK):download completed.
Now go away and create more functions!