How to Make a User with a Numeric Username in Linux (2014)

Note: If you want to have numeric usernames for business reasons, put a letter in front, like . However, some low-level tools assume numbers are options and usernames don’t begin with numbers, so there are systems in place to make it hard to create a numeric username, and careless use of it can lead to chaos. The only low-level program I’ve ever encountered that completely refuses to handle numeric usernames is the suite of tools, which are like a primitive .

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