The expensive random(4) devices referred to don't exist any longer and aren't described in that man page, but it's probably worth mentioning how arc4random(3) is different from rand(3) etc.
Index: arc4random.3 =================================================================== RCS file: /cvs/src/lib/libc/crypt/arc4random.3,v retrieving revision 1.27 diff -u -p -r1.27 arc4random.3 --- arc4random.3 23 Dec 2008 18:31:02 -0000 1.27 +++ arc4random.3 26 Jul 2012 14:55:01 -0000 @@ -69,10 +69,7 @@ which uses 8*8 8-bit S-Boxes. The S-Boxes can be in about (2**1700) states. .Pp .Fn arc4random -fits into a middle ground not covered by other subsystems such as -the strong, slow, and resource expensive random -devices described in -.Xr random 4 +provides a cryptographically secure pseudo-random number generator versus the fast but poor quality interfaces described in .Xr rand 3 , .Xr random 3 , -- Christian "naddy" Weisgerber na...@mips.inka.de
