Golang Multi-threaded file transfer

This is a created article in which the information may have evolved or changed. Golang Multi-threaded file transfer
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Some time ago to use Golang simple implementation of multi-threaded file transfer. The method used to split the files to be transferred into multiple parts is transmitted simultaneously by multiple threads. The service side restores the file stitching to the original file after all the data has been received. After the server is compiled directly, the client needs at least one parameter: The file name to be sent. In additional parameters, the second parameter is the file name that is eventually generated by the specified server. The third parameter is the size of a single send packet (in bytes), up to 18K. The fourth parameter is the number of split files to be sent, which corresponds to how many threads are sent. All right, here's the whole code.