UNIX_MISTAKE, a document which discusses some mistakes that the UNIX operating system seems to foster.
HTML_MISTAKE is available in a C version and a FORTRAN77 version and a FORTRAN90 version and an HTML version and a MATLAB version and a UNIX version.
Unix is prone to obscure and irreversible errors, such as what happens when you accidentally type
rm * .c
Today, I invented a new error. I had two files in one directory, and I wanted to have a copy of both somewhere else. My Ubuntu interface tries to make everything easy, but one thing it can't handle, (or I can't figure out) is how to copy a file. Believe it or not, there are menu items to COPY and COPY TO but neither one seems to actually...copy the damn file.
So I moved both files temporarily to the Desktop, since that's easy to specify on a command line. The files are julia_gpu.cu and julia_cpu.cu. Since their names are similar, it's going to be easy to copy both of them to my current directory with a single command. But instead of typing:
cp ~/Desktop/julia* .
I typed
cp ~/Desktop/julia*
which, as you must realize, is not quite the same thing.
No files were copied to my current directory. In fact, nothing at all happened, or so it seemed. Then I realized that I should have received a snarly Unix message about not specifying a destination for the copy command...so the fact that I didn't get an error message meant that Unix thought it knew what I wanted...and that meant that my actual command had been expanded to the perfectly-reasonable-to-Unix:
cp ~/Desktop/julia_cpu.cu ~/Desktop/julia_gpu.cu
and so one of my files overwrote the other, and now I have two copies
of one file and no copies of the other. I'm just lucky that I realized
what had happened, and in this case knew where another copy of the
obliterated file could be retrieved. That doesn't always happen!
All in all, it's kind of a beautiful error, and only works if there are exactly two matches to the pattern.
If I could figure out how to make money from an error like this, I'd be filling in the patent form right now!
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