[Bug 804355] Re: jot random number generator broken in batch jobs

[James Page]

@SaveTheRbtz

Thanks for the updated patch - that sure is alot of changes!

One of my fellow core-dev's pointed out to me that changing the
structure of the source package is not recommended in Ubuntu as it makes
merging from Debian if/when they change much more difficult - apologies
for the bad advice.

It would make sense to submit these wider impacting changes back to
Debian - please see https://wiki.ubuntu.com/Debian/Bugs for more
information on how todo this.

I've rationalized your revised patch into the original packaging for
upload to Ubuntu.

Please feel free to request that this is backported to Lucid -
https://wiki.ubuntu.com/UbuntuBackports has more details on how todo
this.

Thanks for your contribution to Ubuntu!

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https://bugs.launchpad.net/bugs/804355

Title:
  jot random number generator broken in batch jobs

Status in “athena-jot” package in Ubuntu:
  New

Bug description:
  jot -r generates same random numbers within one second time so it's
  unusable in batch jobs like shell scripts.

  There is code for initializing "random" seed:
      s = (randomize ? time(0) : STEP_DEF);
      /*... snip ....*/
      srand((int) s);

  Here is an example of this behavior:
  rbtz at rbtz-desktop:~$ date +%s; jot -r 1 0 10000000
  1309455778
  9981995
  rbtz at rbtz-desktop:~$ date +%s; jot -r 1 0 10000000
  1309455779
  2355993
  rbtz at rbtz-desktop:~$ date +%s; jot -r 1 0 10000000
  1309455779
  2355993
  rbtz at rbtz-desktop:~$ date +%s; jot -r 1 0 10000000
  1309455779
  2355993
  rbtz at rbtz-desktop:~$ date +%s; jot -r 1 0 10000000
  1309455780
  3745306
  rbtz at rbtz-desktop:~$ date +%s; jot -r 1 0 10000000
  1309455780
  3745306

  As fast fix pid can be added to seed
  srandom((int) s ^ (getpid()<<4));

  As good fix arc4random or similar mechanism can be used.

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