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| From | Keith Thompson <kst-u@mib.org> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: time |
| Date | 2012-11-19 16:51 -0800 |
| Organization | None to speak of |
| Message-ID | <lnd2z9f65y.fsf@nuthaus.mib.org> (permalink) |
| References | <k8ehrs$ddf$1@dont-email.me> <4hjla8hdbe4ft1vjnnv6ppdqd08odelkbg@4ax.com> |
Geoff <geoff@invalid.invalid> writes:
> On Mon, 19 Nov 2012 19:11:41 -0500, "Bill Cunningham"
> <nospam@nspam.invalid> wrote:
>> I am using the time and date in my code using asctime () time(), and
>>localtime(). I know in POSIX they are obsolete but I am concerned with
>>c89-99. strftime() is suppoed to be the function used now. I get the time
>>and date just fine with the code I've written but I want to use the time to
>>seed a random number generator. I don't know if I want seconds from epoch or
>>what. Any input?
>
> srand((unsigned)time(NULL));
The cast is unnecessary. time() returns a value of type time_t,
which is an arithmetic type; it will be implicitly converted to
the appropriate type for the argument to srand() (which, yes,
happens to be unsigned int).
One could argue, I suppose, that the cast makes it more explicit,
but I tend to view all casts with suspicion. Most of them are
either unnecessary or dangerous.
--
Keith Thompson (The_Other_Keith) kst-u@mib.org <http://www.ghoti.net/~kst>
Will write code for food.
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"
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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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