** or --force flags is used, or unless this is a private check-in.
  ** The initial commit MUST have tags "trunk" and "sym-trunk".
  */
  if( !vid ){
    if( sCiInfo.zBranch==0 ){
      if( allowFork==0 && forceFlag==0 && g.markPrivate==0
        && db_exists("SELECT 1 from event where type='ci'") ){
        fossil_fatal("would fork.  \"update\" first or use --allow-fork.");
        fossil_fatal("would fork.  \"update\" first.");
      }
      sCiInfo.zBranch = db_get("main-branch", "trunk");
    }
  }else if( sCiInfo.zBranch==0 && allowFork==0 && forceFlag==0
    && g.markPrivate==0 && !is_a_leaf(vid)
  ){
    fossil_fatal("would fork.  \"update\" first or use --allow-fork.");
    fossil_fatal("would fork.  \"update\" first.");
  }

  /*
  ** Do not allow a commit against a closed leaf unless the commit
  ** ends up on a different branch.
  */
  if(