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Hey Unix history nerds:Do we know who wrote tar(1)? Like, the original tar.c included in V7 Research Unix (which is the earliest one I can find). The list of potential culprits is pretty short, but there's no attribution I can find.(If you have an answer, please clarify where you got it from, and reference any contemporaneous/primary sources if you've got them.)

@piggo @joe @cliffle The jump from the switch is at run-time; at compile-time, the for loop gets compiled as normal, including the "after the body" parts

Many Unix tar programs leak uninitialized data into unused portions of the file. This is not unusual for C programs (unfortunately). The leaked data is usually just repetition of earlier files, so it wasn't obviously useful for anything.Until I noticed that optimizations to tar programs tended to change _which_ earlier data was leaked.Turns out, you can use this behavior to fingerprint the tar implementation pretty precisely in some cases.