Terminal no longer accepting input

No.

I am using an old school sunos if that makes a difference.

I was using nslookup. This is what my manpage says. Doesn't things in brackets mean optional?

NAME
       nslookup - query Internet name servers interactively

SYNOPSIS
       nslookup [-option] [name | -] [server]

DESCRIPTION
       nslookup  is a program to query Internet domain name servers.  nslookup
       has two modes: interactive and non-interactive. Interactive mode allows
       the user to query name servers for information about various hosts  and
       domains  or to print a list of hosts in a domain.  Non-interactive mode
       prints just the name and requested information for a host or domain.

ARGUMENTS
       Interactive mode is entered in the following cases:

       a. when no arguments are given (the default name server is used);

       b. when the first argument is a hyphen (-) and the second  argument  is
          the host name or Internet address of a name server.

       Non-interactive  mode  is used when the name or Internet address of the
       host to be looked up is given as the first argument. The optional  sec-
       ond argument specifies the host name or address of a name server.

       Options  can  also be specified on the command line if they precede the
       arguments and are prefixed with a hyphen. For example,  to  change  the
       default  query  type to host information, with an initial timeout of 10
       seconds, type:

          nslookup -query=hinfo  -timeout=10

       The -version option causes nslookup to print the version number and im-
       mediately exit.

I thought things in brackets was optional? So I did not provide it a server. It seemed to freeze so I pressed ctrl + c. Then nothing seemed to work. It also left a caret > on the screen. The colon is part of my terminal :. It does not bother me so I have not changed it.

: nslookup
>
: ^C

: ^C

Some googling gave me the idea to type reset. Not sure why that helps. Had to type that a few times for it to work.

:
-bash: kijsal: command not found
-bash: kmreset: command not found
:
:

I also googled ctrl + q after you mentioned it above. I found this.

https://web.cecs.pdx.edu/~rootd/catdoc/guide/TheGuide_38.html

This seemed to help. Not sure why ctrl + \ is better than ctrl + c.

<kbd>ctrl-\</kbd>
same as ctrl-c but stronger (used when terminal doesn't respond)

This was the output after I typed ctrl + \.

: nslookup
> Quit (core dumped)