Used to synchronize access to the filecontrolblock.
用于同步对文件控制块的访问。
2
You use the library by opening the document and reading the file, followed by looping through each block in the main control block, as shown in Listing 1.
若要使用这个库，可以打开此文档并读取文件，然后依次循环主控制块内的每个块，如清单1所示。
3
If it is just seconds you are talking about (and not minutes or hours), and you control the server-side, you can have the request processing block until the file is created.