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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 | --- random.3 2004-11-25 11:38:42.000000000 -0800 +++ random.3.edit 2006-07-12 11:25:20.000000000 -0700 @@ -36,32 +36,45 @@ .Dt RANDOM 3 .Os .Sh NAME +.Nm initstate , .Nm random , +.Nm setstate , .Nm srandom , -.Nm srandomdev , -.Nm initstate , -.Nm setstate +.Nm srandomdev .Nd better random number generator; routines for changing generators .Sh LIBRARY .Lb libc .Sh SYNOPSIS .In stdlib.h +.Ft char * +.Fo initstate +.Fa "unsigned seed" +.Fa "char *state" +.Fa "size_t size" +.Fc .Ft long -.Fn random void +.Fo random +.Fa void +.Fc +.Ft char * +.Fo setstate +.Fa "const char *state" +.Fc .Ft void -.Fn srandom "unsigned long seed" +.Fo srandom +.Fa "unsigned seed" +.Fc .Ft void -.Fn srandomdev void -.Ft char * -.Fn initstate "unsigned long seed" "char *state" "long n" -.Ft char * -.Fn setstate "char *state" +.Fo srandomdev +.Fa void +.Fc .Sh DESCRIPTION The .Fn random function -uses a non-linear additive feedback random number generator employing a -default table of size 31 long integers to return successive pseudo-random +uses a non-linear, additive feedback, random number generator, employing a +default table of size 31 long integers. +It returns successive pseudo-random numbers in the range from 0 to .if t 2\u\s731\s10\d\(mi1. .if n (2**31)\(mi1. @@ -82,7 +95,7 @@ .Xr rand 3 produces a much less random sequence \(em in fact, the low dozen bits generated by rand go through a cyclic pattern. -All the bits generated by +All of the bits generated by .Fn random are usable. For example, @@ -102,7 +115,7 @@ .Pp The .Fn srandomdev -routine initializes a state array using the +routine initializes a state array, using the .Xr random 4 random number device which returns good random numbers, suitable for cryptographic use. @@ -127,7 +140,7 @@ the nearest known amount. Using less than 8 bytes will cause an error.) The seed for the initialization (which specifies a starting point for -the random number sequence, and provides for restarting at the same +the random number sequence and provides for restarting at the same point) is also an argument. The .Fn initstate @@ -166,7 +179,7 @@ With 256 bytes of state information, the period of the random number generator is greater than .if t 2\u\s769\s10\d, -.if n 2**69 +.if n 2**69 , which should be sufficient for most purposes. .Sh AUTHORS .An Earl T. Cohen @@ -177,11 +190,36 @@ .Fn setstate detects that the state information has been garbled, error messages are printed on the standard error output. +.Sh LEGACY SYNOPSIS +.Fd #include <stdlib.h> +.Pp +.Ft char * +.br +.Fo initstate +.Fa "unsigned long seed" +.Fa "char *state" +.Fa "long size" +.Fc ; +.Pp +.Ft char * +.br +.Fo setstate +.Fa "char *state" +.Fc ; +.Pp +.Ft void +.br +.Fo srandom +.Fa "unsigned long seed" +.Fc ; +.Pp +The type of each parameter is different in the legacy version. .Sh SEE ALSO .Xr arc4random 3 , .Xr rand 3 , .Xr srand 3 , -.Xr random 4 +.Xr random 4 , +.Xr compat 5 .Sh HISTORY These functions appeared in |