4 arg select as an alternative to Time::HiRes ?

Limbic~Region has asked for the wisdom of the Perl Monks concerning the following question:

All:
Is there anything evil about the following:

#!/usr/bin/perl -w
use strict;
print "awake\n";
select(undef,undef,undef,.75);
print "awake\n";
[download]

Using the 4 arg select to sleep for sub 1 second intervals without Time::HiRes.

I am strictly asking if there is anything wrong with it. I came across it and thought it was neat and do not think it is an excuse not to use Time::HiRes.

Thanks - L~R

Comment on 4 arg select as an alternative to Time::HiRes ? Download Code

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Re: 4 arg select as an alternative to Time::HiRes ? by IlyaM (Parson) on Mar 01, 2003 at 22:39 UTC
There is nothing wrong with it. This method is even documented in perl FAQ: How can I sleep() or alarm() for under a second?. -- Ilya Martynov, ilya@iponweb.net CTO IPonWEB (UK) Ltd Quality Perl Programming and Unix Support UK managed @ offshore prices - http://www.iponweb.net Personal website - http://martynov.org	[reply]
Re: Re: 4 arg select as an alternative to Time::HiRes ? by Limbic~Region (Chancellor) on Mar 01, 2003 at 22:48 UTC
IlyaM, Thanks and duh - now I remember where I came across it (Perldoc's FAQ). Cheers - L~R	[reply]
Re: 4 arg select as an alternative to Time::HiRes ? by Abigail-II (Bishop) on Mar 02, 2003 at 12:31 UTC
Your really don't have to excuse yourself for not using Time::HiRes. Time::HiRes was only a recent addition to the core anyway. Furthermore, if you look into the XS file, you'll notice that depending on what's available on your platform, Time::HiRes may fall back on `select` anyway. Abigail	[reply] [d/l]
Re: 4 arg select as an alternative to Time::HiRes ? by crenz (Priest) on Mar 01, 2003 at 23:19 UTC
Well, it's definitely not evil, but for someone like me who is not so well-versed in Unix system calls or whatever select does, the Time::HiRes variant is much more self-documenting :)	[reply]
Re: 4 arg select as an alternative to Time::HiRes ? by Aristotle (Chancellor) on Mar 02, 2003 at 01:04 UTC
You could also try this for size: `BEGIN { CORE::sleep = sub(;$) { select((undef)x3, shift) } } sleep 0.75;` [download] Makeshifts last the longest.*	[reply] [d/l]
Re: Re: 4 arg select as an alternative to Time::HiRes ? by BrowserUk (Patriarch) on Mar 02, 2003 at 01:57 UTC
I can never get select to accept `(undef)x3,$time`? I also found that substr won't accept an array for its argument list either? Examine what is said, not who speaks. 1) When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong. 2) The only way of discovering the limits of the possible is to venture a little way past them into the impossible 3) Any sufficiently advanced technology is indistinguishable from magic. Arthur C. Clarke.	[reply] [d/l]
Re^3: 4 arg select as an alternative to Time::HiRes ? by Aristotle (Chancellor) on Mar 02, 2003 at 02:06 UTC
`$ perl -le'print for prototype("CORE::substr"), prototype("CORE::selec +t")' $$;$;$ ;` [download] You are right about substr. Unfortunately, select seems to have some special magic; even the error message you get is unique to it. One more thing to remember.. Makeshifts last the longest.*	[reply] [d/l]
Re: Re^3: 4 arg select as an alternative to Time::HiRes ? by BrowserUk (Patriarch) on Mar 02, 2003 at 13:12 UTC