Error throwing after program finishes

[Vedvart 0]

I wrote a program intended to update an entire github repo into the files in my opencomputers computer. It runs successfully, creating all necessary folders and downloading all relevant files successfully, but after the code completes, throws the following error:

/bin/sh.lua:14: attempt to index a nil value (field 'stdin')
stack traceback:
		  init:18: in function <init:17>
          (...tail calls...)
          /bin/sh.lua:14: in main chunk
          [C]: in function 'xpcall'
          machine:798: in global 'xpcall'
          init:17: in local 'init'
          bios:64: in main chunk

Googling this issue turned up no great results, and I can't think of anything in my code that is causing this. My full code is below; any help resolving this is appreciated.

internet = require("internet")
io = require("io")
filesystem = require("filesystem")
handle = internet.request("https://api.github.com/repos/Vedvart/Minecraft/contents")

result = ""

for chunk in handle do result = result..chunk end

while(not (string.find(result, "download_url") == nil)) do

  i, j = string.find(result, "download_url")
  qi, qj = string.find(string.sub(result, j+4,-1), '"')

  url = string.sub(result, j + 4, j + qi + 2)

  if string.sub(url, -14) == '.gitattributes' then goto continue end
  
  ni, nj = string.find(url, "Vedvart")
  filepath = string.sub(url, nj+2, -1)

  ri, rj = string.find(string.reverse(filepath), "/")
  if not filesystem.isDirectory("/home/github/"..string.sub(filepath, 1, -ri)) then
    print('had to make')
    filesystem.makeDirectory("/home/github/"..string.sub(filepath, 1, -ri))
  end
  print('here 2')

  file_content_handle = internet.request(url)
  file_content = ''
  for chunk in file_content_handle do file_content = file_content .. chunk end

  print(filepath)
  print(io)
  print(filesystem.isDirectory("/home/github/"..string.sub(filepath, 1, -ri)))

  file = io.open('/home/github/'..filepath, 'w')
  print(file)
  file:write(file_content)
  file:close()

  print('here 3')
  print(file)

  ::continue::
  result = string.sub(result, j+qi+3, -1)

  print('here 4')

end

print('done')

os.exit()

print('why are you here')