linux console

Older gnuplot versions required special terminals linux or vgagl in order to display graphics on the linux console, i.e. in the absence of X11 or other windowing environment. These terminals have been deprecated.

The recommended way to run gnuplot from the linux console is now to use a console terminal emulator such as yaft (https://github.com/uobikiemukot/yaft) that supports sixel graphics. With yaft as your console terminal you can run gnuplot and select a terminal with sixel output. See sixelgd. As a fall-back option you could use set term dumb, but sixel graphics are much nicer.