change to StatusEOF approach

base/util.jl

@@ -287,37 +287,40 @@ greater than 0 can be provided, after which the default will be returned.
 
 See also `Base.getpass` and `Base.winprompt` for secure entry of passwords.
 """
-function prompt(input::IO, output::IO, message::AbstractString; default::AbstractString="", timeout::Union{Nothing, Int} = nothing)
+function prompt(input::IO, output::IO, message::AbstractString; default::AbstractString="", timeout::Union{Nothing, Real} = nothing)
+    timedout = false
+    uinput_entered = false
     if !isnothing(timeout) && timeout > 0
         plural = timeout == 1 ? "" : "s"
         msg = !isempty(default) ? "$message [$default] timeout $timeout second$(plural): " : "$message: "
-        timeout_timer = Timer(timeout)
+        Timer(timeout) do t
+            uinput_entered && return
+            timedout = true
+            lock(input.cond)
+            input.status = Base.StatusEOF
+            notify(input.cond)
+            unlock(input.cond)
+        end
     else
         msg = !isempty(default) ? "$message [$default]: " : "$message: "
         timeout_timer = nothing
     end
     print(output, msg)
-    t = @async readline(input, keep=true)
-    while !istaskdone(t) && (!isnothing(timeout_timer) && isopen(timeout_timer))
-        sleep(0.1)
-    end
-    if !isnothing(timeout_timer) && !istaskdone(t)
-        try
-            Base.throwto(t, InterruptException())
-        catch
-        end
+    uinput = readline(input, keep=true)
+    if timedout
         println(output, "timed out")
         return default
+    else
+        uinput_entered = true # disable timeout action
     end
-    uinput = fetch(t)
     isempty(uinput) && return nothing  # Encountered an EOF
     uinput = chomp(uinput)
     isempty(uinput) ? default : uinput
 end
 
 # allow new prompt methods to be defined if stdin has been
 # redirected to some custom stream, e.g. in IJulia.
-prompt(message::AbstractString; default::AbstractString="",timeout::Union{Nothing, Int} = nothing) = prompt(stdin, stdout, message, default=default, timeout=timeout)
+prompt(message::AbstractString; default::AbstractString="",timeout::Union{Nothing, Real} = nothing) = prompt(stdin, stdout, message, default=default, timeout=timeout)
 
 # Windows authentication prompt
 if Sys.iswindows()