I have tried wall, but it does not show the message to local terminal. Can I show it to local terminal, too? The remote SSH and the local GUI terminal are the same user account.
The reason why I am trying to do is that I want to use it basically for "copy and paste" between host and guest (VM), when the hypervisor's "copy and paste" feature is not working. I could save the text to a text file and then reload it on the guest, but just displaying the text like wall would be easier.
wall is a message broadcast facility for the local machine on which it's run. There is no capability for sending messages to remote systems. (See man wall for further information.)
If you're logged in from to a remote system with something like ssh, and wall is run on that remote system, the message will be displayed on all logged-in terminals. This will include the one hosting your ssh session.
Note that unless you a superuser, you can only write to terminals owned by other users where the user has not used mesg n (a default in a number of distributions' .profile files). The superuser can write everywhere regardless, and a user can always write to terminals logged in with their own user account.
If you're trying to send messages between two of your own terminals you might find write a little more focussed (see man write):
write roaima .... [Ctrl/D] Or, for specific direction to the user roaima logged on to terminal /dev/pts/0:
write roaima pts/0 .... [Ctrl/D] Some systems also include talk, xtalk, ytalk, phone, or one of a similar slew of applications. If these are installed on directly reachable systems it is possible to connect sessions across the network. (Note that I haven't tried these in well over ten years so they may be seriously obsolete.)
write myid pts/1, the SSH window says broadcast from pts/0, and message can be sent. But if I do `write myid pts/0' in the SSH window, it says that the account is not logged in on pts/0. pts/0. You can find out what tty you're on with the tty command utmp records. That's why write might fail with an error message for you. If you want to send a message to one of your own terminals, you might just do echo message > /dev/pts/0 or alike.
wallandwriterely on theutmprecords. Not every terminal emulator updates these records, in some it's a config option, while some others don't support updating these records at all (you might launch an external helper utility to maintain these records).