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Re: time

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On 11/21/2012 11:30 AM, Anand Hariharan wrote:
> On Nov 19, 9:07 pm, Nobody <nob...@nowhere.com> wrote:
>>
>> The simple solution is srand(time(NULL)). However, time() only has a one
>> second resolution, so consecutive invocations of the program may produce
>> identical results.
> 
> Given an application for which, the standard rand family of functions
> is sufficient, why would one want to make consecutive invocations to
> srand?

Keep in mind that he's talking about consecutive invocations of the
entire program, not consecutive calls to srand() within a single program.

I heard that there are servers out there that are capable of handling
dozens or even hundreds of requests in a single second (I don't claim to
have any personal experience with such things), and spawn a fresh copy
of some program to handle each request. If srand(time(NULL)) were used
in that program, it would generate the same exact sequence of random
numbers for all requests received during the same second. For some
possible uses, that would not be acceptable.

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time "Bill Cunningham" <nospam@nspam.invalid> - 2012-11-19 19:11 -0500
  Re: time Geoff <geoff@invalid.invalid> - 2012-11-19 16:26 -0800
    Re: time Keith Thompson <kst-u@mib.org> - 2012-11-19 16:51 -0800
      Re: time Geoff <geoff@invalid.invalid> - 2012-11-19 17:01 -0800
      Re: time "Bill Cunningham" <nospam@nspam.invalid> - 2012-11-19 20:07 -0500
        Re: time Keith Thompson <kst-u@mib.org> - 2012-11-19 23:54 -0800
          Re: time pete <pfiland@mindspring.com> - 2012-11-20 07:31 -0500
          Re: time "Bill Cunningham" <nospam@nspam.invalid> - 2012-11-20 17:09 -0500
  Re: time Keith Thompson <kst-u@mib.org> - 2012-11-19 16:30 -0800
    Re: time "Bill Cunningham" <nospam@nspam.invalid> - 2012-11-19 20:04 -0500
      Re: time Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-11-25 05:52 -0800
  Re: time Nobody <nobody@nowhere.com> - 2012-11-20 03:07 +0000
    Re: time Keith Thompson <kst-u@mib.org> - 2012-11-19 23:58 -0800
    Re: time Anand Hariharan <mailto.anand.hariharan@gmail.com> - 2012-11-21 08:30 -0800
      Re: time "osmium" <r124c4u102@comcast.net> - 2012-11-21 11:11 -0600
      Re: time James Kuyper <jameskuyper@verizon.net> - 2012-11-21 12:22 -0500
        Re: time gof@somewhere.invalid (Adam Wysocki) - 2012-11-21 19:09 +0000
          Re: time Keith Thompson <kst-u@mib.org> - 2012-11-21 12:01 -0800
            Re: time gof@somewhere.invalid (Adam Wysocki) - 2012-11-23 08:15 +0000
          Re: time "Bill Cunningham" <nospam@nspam.invalid> - 2012-11-21 15:16 -0500
            Re: time "osmium" <r124c4u102@comcast.net> - 2012-11-21 14:23 -0600
              Re: time Rosario1903 <Rosario@invalid.invalid> - 2012-11-22 10:25 +0100
            Re: time Keith Thompson <kst-u@mib.org> - 2012-11-21 12:30 -0800
              Re: time "Bill Cunningham" <nospam@nspam.invalid> - 2012-11-21 18:24 -0500
            Re: time Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-11-25 05:56 -0800
          Re: time Nobody <nobody@nowhere.com> - 2012-11-22 02:00 +0000
            Re: time Keith Thompson <kst-u@mib.org> - 2012-11-21 19:57 -0800
              Re: time gof@somewhere.invalid (Adam Wysocki) - 2012-11-23 08:31 +0000
            Re: time army1987 <army1987@ask-for-it.invalid> - 2012-11-24 13:58 +0000
          Re: time Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-11-22 11:36 +0000
            Re: time gof@somewhere.invalid (Adam Wysocki) - 2012-11-23 08:20 +0000
              Re: time Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-11-23 14:31 +0000
      Re: time Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-11-25 05:54 -0800
  Re: time Mark Storkamp <mstorkamp@yahoo.com> - 2012-11-20 08:34 -0600
    Re: time "Bill Cunningham" <nospam@nspam.invalid> - 2012-11-20 20:37 -0500
      Re: time Keith Thompson <kst-u@mib.org> - 2012-11-20 20:25 -0800
        Re: time "Bill Cunningham" <nospam@nspam.invalid> - 2012-11-21 15:11 -0500

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