Function luaopen_io

lib/lua/src/liolib.c:534–552

LUALIB_API int luaopen_io (lua_State *L) {
  createmeta(L);
  /* create (private) environment (with fields IO_INPUT, IO_OUTPUT, __close) */
  newfenv(L, io_fclose);
  lua_replace(L, LUA_ENVIRONINDEX);
  /* open library */
  luaL_register(L, LUA_IOLIBNAME, iolib);
  /* create (and set) default files */
  newfenv(L, io_noclose);  /* close function for default files */
  createstdfile(L, stdin, IO_INPUT, "stdin");
  createstdfile(L, stdout, IO_OUTPUT, "stdout");
  createstdfile(L, stderr, 0, "stderr");
  lua_pop(L, 1);  /* pop environment for default files */
  lua_getfield(L, -1, "popen");
  newfenv(L, io_pclose);  /* create environment for 'popen' */
  lua_setfenv(L, -2);  /* set fenv for 'popen' */
  lua_pop(L, 1);  /* pop 'popen' */
  return 1;
}