Sun Apr 3 13:00:39 CEST 2011
| os.execute ([command])
| This function is equivalent to the C function system. It passes
| command to be executed by an operating system shell. It returns
| a status code, which is system-dependent. If command is absent,
| then it returns nonzero if a shell is available and zero otherwise.
An empty string does not crash. But it does not help, because
I want to use the variant without argument.
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