add linenoise.readLineStatus to get status (eg: ctrl-D or ctrl-C) (#16977)

* add linenoise.readLineStatus to get status (eg: ctrl-D or ctrl-C)

* changelog

lib/impure/rdstdin.nim

@@ -12,16 +12,18 @@
 ## (e.g. you can navigate with the arrow keys). On Windows ``system.readLine``
 ## is used. This suffices because Windows' console already provides the
 ## wanted functionality.
-##
-## **Examples:**
-##
-## .. code-block:: nim
-##   echo readLineFromStdin("Is Nim awesome? (Y/n):")
-##   var userResponse: string
-##   doAssert readLineFromStdin("How are you?:", line = userResponse)
-##   echo userResponse
 
-when defined(Windows):
+runnableExamples:
+  if false:
+    echo readLineFromStdin("Is Nim awesome? (Y/n): ")
+    var line: string
+    while true:
+      let ok = readLineFromStdin("How are you? ", line)
+      if not ok: break # ctrl-C or ctrl-D will cause a break
+      if line.len > 0: echo line
+    echo "exiting"
+
+when defined(windows):
   proc readLineFromStdin*(prompt: string): string {.
                           tags: [ReadIOEffect, WriteIOEffect].} =
     ## Reads a line from stdin.