xsel

xsel

TLDR

Use a command's output as input of the clip[b]oard (equivalent to Ctrl + C)

$ echo 123 | xsel -ib
copy

Use the contents of a file as input of the clipboard

$ cat [file] | xsel -ib
copy

Output the clipboard's contents into the terminal (equivalent to Ctrl + V)

$ xsel -ob
copy

Output the clipboard's contents into a file

$ xsel -ob > [file]
copy

Clear the clipboard

$ xsel -cb
copy

Output the X11 primary selection's contents into the terminal (equivalent to a mouse middle-click)

$ xsel -op
copy

Copied to clipboard
Dodo Farming