Merge branch 'thliebig-master'

pyvisa-py/tcpip.py

@@ -12,6 +12,7 @@
 
 import random
 import socket
+import select
 import time
 
 from pyvisa import constants, attributes
@@ -333,11 +334,10 @@ def after_parsing(self):
  # TODO: board_number not handled
 
  self.interface = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
-
  self.interface.setblocking(0)
 
  try:
- self.interface.connect((self.parsed.host_address, self.parsed.port))
+ self.interface.connect_ex((self.parsed.host_address, int(self.parsed.port)))
  except Exception as e:
  raise Exception("could not create socket: %s" % e)
 
@@ -374,7 +374,7 @@ def read(self, count):
 
  end_byte = common.int_to_byte(end_char) if end_char else b''
 
- read_fun = self.socket.recv
+ read_fun = self.interface.recv
 
  now = start = time.time()
 
@@ -387,6 +387,8 @@ def read(self, count):
  constants.StatusCode.success_termination_character_read)
 
  while now - start <= timeout:
+ # use select to wait for read ready
+ select.select([self.interface], [], [])
  last = read_fun(chunk_length)
 
  if not last:
@@ -429,7 +431,9 @@ def write(self, data):
  block = data[offset:min(offset+chunk_size, sz)]
 
  try:
- size = self.socket.send(block)
+ # use select to wait for write ready
+ select.select([], [self.interface], [])
+ size = self.interface.send(block)
  except socket.timeout as e:
  return offset, StatusCode.error_io