I am making it so that it stops asking for input upon CTRL-C.
What I have currently is that a separate go-routine, upon receiving a CTRL-C, changes the value of a variable so it won't ask for another line. However, I can't seem to find a way around the current line.
i.e. I still have to press enter once, to get out of the current iteration of reading for .
Is there perhaps a way to push a " " into stdin for the reader.ReadString to read. Or a way to stop its execution altogether.
The only decent mechanism that Go gives you to proceed when either of two things happens is select, and select only selects on channel reads, so your only option is to change your signal-handler goroutine to write to a channel, and add another goroutine that handles stdin and passes lines of input to a channel, then select on the two channels.
However, that still leaves your question half-unanswered: your main program can stop waiting for input on a Ctrl-C, but the goroutine that's reading input will still be waiting for input. In some cases that might be okay... if you will never need stdin again, or if you will go right back to processing lines in the same exact way. But if you want to do something other than ReadString from that reader, you're stuck... literally. The only solution I see would be to write your own state machine around Read or ReadByte that is capable of changing its behavior in response to external conditions, but that can easily get horribly complicated.
Basically, this looks like a case where Go simplifies things compared to the underlying system (not exposing anything like EINTR, not allowing select on filehandles), but ends up providing less power to the programmer.