Jose E. Marchesi wrote: > Note that my reason for preferring random to random_r in code which must > not be reentrant is the not documented requirement of memsetting the > random_data passed to initstate_r to zeroes. Even if that trick works > with the current versions of glibc (and the random_r module from gnulib) > AFAIK nothing guarantees that it will work in the future.
Good point. I have registered a glibc manual bug about it: http://sourceware.org/bugzilla/show_bug.cgi?id=13595 My understanding is that - The memset() is necessary, and is part of BSD culture. - The initstate_r() call is only necessary if you want truly different numbers at each program run. [1] says: "If initstate() has not been called, then random() shall behave as though initstate() had been called with seed=1 and size=128." Bruno [1] http://pubs.opengroup.org/onlinepubs/9699919799/functions/initstate.html
