old_contents: #!/usr/bin/env python
  
  # Copyright (c) 2019, IRIS-HEP
  # All rights reserved.
  #
  # Redistribution and use in source and binary forms, with or without
  # modification, are permitted provided that the following conditions are met:
  #
  # * Redistributions of source code must retain the above copyright notice, this
  #   list of conditions and the following disclaimer.
  #
  # * Redistributions in binary form must reproduce the above copyright notice,
  #   this list of conditions and the following disclaimer in the documentation
  #   and/or other materials provided with the distribution.
  #
  # * Neither the name of the copyright holder nor the names of its
  #   contributors may be used to endorse or promote products derived from
  #   this software without specific prior written permission.
  #
  # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  # DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  # SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  # CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  import sys
  import os
  sys.path.insert(0, os.path.abspath('../..'))
  
  import uproot
  
  import subprocess
  import json
  
  # Make sure c file is named allstreamers.c
  subprocess.run("root -l -q dev/allstreamers.c", shell=True)
  
  f = uproot.open("dev/allstreamers.root")
  
  # Check with json
  data = json.load(open("dev/streamerversions.json"))
  for x in f._context.streamerinfos:
      if data[x._fName.decode("ascii")] != x._fClassVersion:
          print("Old {0} version = {1}. New {0} version = {2}".format(x._fName, data[x._fName.decode("ascii")], x._fClassVersion))
  
  tkey = uproot.rootio.TKey.read(f._context.source, uproot.source.cursor.Cursor(f._context.tfile["_fSeekInfo"]), None, None)
  start = f._context.tfile["_fSeekInfo"] + tkey._fKeylen
  streamerlen = tkey._fObjlen
  
  with open("dev/allstreamers.root", "rb") as binary_file:
      binary_file.seek(start)
      couple_bytes = binary_file.read(streamerlen + 1)
  streamers = "streamers = {0}".format(repr(couple_bytes))
  
  lines = []
  for line in open("uproot/write/streamers.py"):
      if line.startswith("streamers"):
          lines.append(streamers)
      else:
          lines.append(line)
  
  with open("uproot/write/streamers.py", "w") as streamerfile:
      for line in lines:
          streamerfile.writelines(line)
  
  os.remove("dev/allstreamers.root")
  
new_contents: #!/usr/bin/env python
  
  # Copyright (c) 2019, IRIS-HEP
  # All rights reserved.
  #
  # Redistribution and use in source and binary forms, with or without
  # modification, are permitted provided that the following conditions are met:
  #
  # * Redistributions of source code must retain the above copyright notice, this
  #   list of conditions and the following disclaimer.
  #
  # * Redistributions in binary form must reproduce the above copyright notice,
  #   this list of conditions and the following disclaimer in the documentation
  #   and/or other materials provided with the distribution.
  #
  # * Neither the name of the copyright holder nor the names of its
  #   contributors may be used to endorse or promote products derived from
  #   this software without specific prior written permission.
  #
  # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  # DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  # SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  # CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  import sys
  import os
  sys.path.insert(0, os.path.abspath('../..'))
  
  import uproot
  
  import subprocess
  import json
  
  # Make sure c file is named allstreamers.c
  subprocess.run("root -l -q dev/allstreamers.c", shell=True)
  
  f = uproot.open("dev/allstreamers.root")
  
  # Check with json
  data = json.load(open("dev/streamerversions.json"))
  for x in f._context.streamerinfos:
      if data[x._fName.decode("ascii")] != x._fClassVersion:
          print("Old {0} version = {1}. New {0} version = {2}".format(x._fName, data[x._fName.decode("ascii")], x._fClassVersion))
  
  tkey = uproot.rootio.TKey.read(f._context.source, uproot.source.cursor.Cursor(f._context.tfile["_fSeekInfo"]), None, None)
  start = f._context.tfile["_fSeekInfo"] + tkey._fKeylen
  streamerlen = tkey._fObjlen
  
  with open("dev/allstreamers.root", "rb") as binary_file:
      binary_file.seek(start)
      couple_bytes = binary_file.read(streamerlen)
  streamers = "streamers = {0}".format(repr(couple_bytes))
  
  lines = []
  for line in open("uproot/write/streamers.py"):
      if line.startswith("streamers"):
          lines.append(streamers)
      else:
          lines.append(line)
  
  with open("uproot/write/streamers.py", "w") as streamerfile:
      for line in lines:
          streamerfile.writelines(line)
  
  os.remove("dev/allstreamers.root")
  
subject: Fix length of streamers