Hello Keith,
On 11/9/18 1:20 AM, Keith Thompson wrote:
> The strfry(3) function does not use rand(). The original version from
> 1995 did, but it was
> changed to use a different PRNG in glibc commit
> 4770745624b7f7f25623f1f10d46a4c4d6aec25c,
> 1996-12-04.
>
> This C program demonstrates the behavior. By not calling srand(), it
> gets the same values
> for successive calls to rand(), but strfry() returns a different value
> each time the program is run.
> If strfry() called srand(), it would alter the sequence of numbers
> return by rand().
>
> #define _GNU_SOURCE
> #include <stdio.h>
> #include <string.h>
> #include <stdlib.h>
> int main(void) {
> printf("%d\n", rand());
> char alphabet[] = "abcdefghijklmnopqrstuvwxyz";
> puts(strfry(alphabet));
> printf("%d\n", rand());
> }
Thanks for the very detailed commit message! Patch applied.
Cheers,
Michael
> Patch follows:
>
> commit e7be0424538b50d49817200ccafc56cf742813bf (HEAD -> kst-strfry)
> Author: Keith Thompson <Keith.S.Thompson@xxxxxxxxx>
> Date: 2018-11-08 16:09:06 -0800
>
> man3/strfry.3: Remove incorrect reference to rand(3)
>
> diff --git man3/strfry.3 man3/strfry.3
> index a4c02435d..5beefa42c 100644
> --- man3/strfry.3
> +++ man3/strfry.3
> @@ -42,10 +42,7 @@ The
> .BR strfry ()
> function randomizes the contents of
> .I string
> -by
> -using
> -.BR rand (3)
> -to randomly swap characters in the string.
> +by randomly swapping characters in the string.
> The result is an anagram of
> .IR string .
> .SH RETURN VALUE
>
--
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/
