random(?)

[Christos Ricudis]

Hello Linux-greek-users!

  On 12 Feb 99, Linux-greek-users wrote to All with subject "random(?)":


 L> Ti diafora exei to /dev/random apo to rand() tis libc?
 L> Xrhsimopoiei to ena to allo h einai asxeta? 
 L> Apo to documentation tou pyrhna eida oti
 L> to /dev/random einai: Nondeterministic random number generator...
 L> Xereis kapoios pws to petyxainei auto? To /dev/random einai koino
 L> sta unixes? thanx.

H rand() ths libc einai enas klassikos Linear Congruential Generator, kai
malista enas arketa kakos - ean h ylopoihsh toy einai kata to gramma toy ANSI
protypoy. 

To /dev/random dhmiourgei random numbers kanontas md5 hashing se non-
deterministic data poy pairnei apo to periballon - to xronismo metaksy twn
keyboard interrupts, ta scan codes poy eisagontai, thn 8esh toy pontikarou, to
xronismo metaksy disk accesses, ktl ktl ktl. Einai arketa palia idea sthn
pragmatikothta, kai ayth einai mia poly kalh ylopoihsh ths. 8a htan poly omorfo
an h rand() ths glibc xrhsimopoiouse to /dev/random sto linux. 

Kai, oxi, paromoio pragma den yparxei by default toulaxiston se kanena allo
Unix poy gnwrizw. 

--
Christos Ricudis
Prof:    So the American government went to IBM to come up with a data
         encryption standard and they came up with ...
Student: EBCDIC!
--
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