terminal_block <-content: what=[{command,output,all}] -> stringNew string with the text of the block; what as for terminal_block->select.
Lines are separated by a single newline, as terminal_block<-contents
does. A part that has not been reached yet -- the output of a command
still running -- reaches to where the client is writing.
command is what was typed: it stops short of the return
that entered it, and passes over the continuation prompt in front of
each line of a command the client collected over several. all
keeps both, being the text of the window.
