How to copy files in Go
A robust and efficient copy is conceptually simple, but not simple to implement due to the need to handle a number of edge cases and system limitations that are imposed by the target operating system and it’s configuration. If you simply want to make a duplicate of the existing file you can use os.Link(srcName, dstName). This avoids having to move bytes around in the application and saves disk space. For large files, this is a significant time and space saving.
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