! <shell command> <command> `<shell command>` ...
Shell commands can be executed from within PyXPlot by pre-fixing them with pling (!) characters, for example:
!mkdir foo
As an alternative, back-quotes (‘) can be used to substitute the output of a shell command into a PyXPlot command, for example:
set xlabel `echo "'" ; ls ; echo "'"`
Note that back-quotes cannot be used inside quote characters, and so the following would not work:
set xlabel '`ls`'