When an interactive fish starts, it executes fish_greeting and displays its output.
The default fish_greeting is a function that prints a variable of the same name (``$fish_greeting``), so you can also just change that if you just want to change the text.
While you could also just put ``echo`` calls into config.fish, fish_greeting takes care of only being used in interactive shells, so it won't be used e.g. with ``scp`` (which executes a shell), which prevents some errors.
Example
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A simple greeting:
::
function fish_greeting
echo Hello friend!
echo The time is (set_color yellow; date +%T; set_color normal) and this machine is called $hostname
