Move eagain logging to run-time switch instead of compile-time switch

README.md

@@ -53,7 +53,7 @@ The examples are commented to better understand how zmq works.
 
 ### Log EAGAIN errno
 
-Sometimes EAGAIN error happens in ZMQ context; typically this is a non-ctritical error that can be ignored. Nonetheless, if you desire to logg or display such error you can compile with the flag ``-d:zmqEAGAIN`` and EAGAIN error will be logged using ``std/logging`` or ``echo`` to stdout if no logger handler is defined.
+Sometimes EAGAIN error happens in ZMQ context; typically this is a non-ctritical error that can be ignored. Nonetheless, if you desire to log or display such error, it is possible to enable it using the ``enableLogEagain`` and disable it with ``disableLogEagain``.
 
 ### Setting default flag as DONTWAIT
 

zmq/connections.nim

@@ -32,13 +32,23 @@ proc zmqError*() {.noinline, noreturn.} =
   e.msg = &"Error: {e.error}. " & $strerror(e.error)
   raise e
 
+var shouldLogEagainError = false
+
+proc enableLogEagain*() =
+  ## Enable logging EAGAIN error in ZMQ calls
+  shouldLogEagainError = true
+
+proc disableLogEagain*() =
+  ## Disable logging EAGAIN error in ZMQ calls
+  shouldLogEagainError = false
+
 proc zmqErrorExceptEAGAIN() =
   var e: ref ZmqError
   new(e)
   e.error = errno()
   let errmsg = $strerror(e.error)
   if e.error == ZMQ_EAGAIN:
-    when defined(zmqEAGAIN):
+    if shouldLogEagainError:
       if logging.getHandlers().len() > 0:
         warn(errmsg)
       else: