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| From | Keith Thompson <kst-u@mib.org> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: solution allocation of memory and composite numbers |
| Date | 2014-12-27 21:52 -0800 |
| Organization | None to speak of |
| Message-ID | <lntx0gxqvr.fsf@nuthaus.mib.org> (permalink) |
| References | (8 earlier) <877fxegj8f.fsf@bsb.me.uk> <1ecde9d0-2198-4d06-a324-222af341db20@googlegroups.com> <87k31cg3kr.fsf@bsb.me.uk> <b64e8dbb-b2af-4d99-a06d-df48ac232df7@googlegroups.com> <x9GdnVgYDYKmqwLJnZ2dnUU7-UOdnZ2d@giganews.com> |
Vincenzo Mercuri <nomail@yahoo.it> writes:
> Il 27/12/2014 23:07, Malcolm McLean ha scritto:
> ..
>> atoi() should be fine. If the number of parameters is wrong or the
>> numbers are out of range, it's easy and natural to put in the
>> checks. [..]
>
> atoi() is not guaranteed to set errno on error either and like
> scanf() has undefined behavior when the value of the result
> cannot be represented.
You're right about the undefined behavior. Somehow I had managed to
miss that. The lesson is, when checking the standard, to check the
parent section for the function you're looking up as well as the section
that describes the function itself.
In this case, N1570 7.22.1.2 describes atoi, atol, and atoll, and says:
Except for the behavior on error, they are equivalent to ...
followed by calls to strtol and stroll. For atoi, the equivalent is:
(int)strtol(nptr, (char **)NULL, 10)
But the parent section, 7.22.1, says:
The functions atof, atoi, atol, and atoll need not affect the
value of the integer expression errno on an error. If the value
of the result cannot be represented, the behavior is undefined.
(And if I'm the only one who didn't notice that, congratulations to
everyone else for being more observant than me.)
--
Keith Thompson (The_Other_Keith) kst-u@mib.org <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"
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solution allocation of memory and composite numbers Dexterr <dejangru@gmail.com> - 2014-12-24 05:52 -0800
Re: solution allocation of memory and composite numbers Dexterr <dejangru@gmail.com> - 2014-12-24 05:55 -0800
Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-24 06:41 -0800
Re: solution allocation of memory and composite numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-12-24 20:16 +0000
Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-24 12:39 -0800
Re: solution allocation of memory and composite numbers Richard Heathfield <invalid@see.sig.invalid> - 2014-12-24 21:22 +0000
Re: solution allocation of memory and composite numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-12-24 22:33 +0000
Re: solution allocation of memory and composite numbers Richard Heathfield <invalid@see.sig.invalid> - 2014-12-25 00:54 +0000
Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-24 18:38 -0800
Re: solution allocation of memory and composite numbers Vincenzo Mercuri <nomail@yahoo.it> - 2014-12-25 12:07 +0100
Re: solution allocation of memory and composite numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-12-26 22:05 +0000
Re: solution allocation of memory and composite numbers BartC <bc@freeuk.com> - 2014-12-26 22:33 +0000
Re: solution allocation of memory and composite numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-12-27 22:08 +0000
Re: solution allocation of memory and composite numbers BartC <bc@freeuk.com> - 2014-12-27 23:28 +0000
Re: solution allocation of memory and composite numbers BartC <bc@freeuk.com> - 2014-12-29 18:34 +0000
Re: solution allocation of memory and composite numbers raltbos@xs4all.nl (Richard Bos) - 2014-12-30 19:23 +0000
Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-26 15:43 -0800
Re: solution allocation of memory and composite numbers Keith Thompson <kst-u@mib.org> - 2014-12-26 15:59 -0800
Re: solution allocation of memory and composite numbers Vincenzo Mercuri <nomail@yahoo.it> - 2014-12-27 14:45 +0100
Re: solution allocation of memory and composite numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-12-27 21:55 +0000
Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-27 14:07 -0800
Re: solution allocation of memory and composite numbers Vincenzo Mercuri <nomail@yahoo.it> - 2014-12-27 23:44 +0100
Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-27 15:49 -0800
Re: solution allocation of memory and composite numbers Keith Thompson <kst-u@mib.org> - 2014-12-27 21:52 -0800
Re: solution allocation of memory and composite numbers Vincenzo Mercuri <nomail@yahoo.it> - 2014-12-28 15:54 +0100
Re: solution allocation of memory and composite numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-12-28 00:03 +0000
Re: solution allocation of memory and composite numbers Keith Thompson <kst-u@mib.org> - 2014-12-26 17:13 -0800
Re: solution allocation of memory and composite numbers Geoff <geoff@invalid.invalid> - 2014-12-27 10:23 -0800
Re: solution allocation of memory and composite numbers Stephen Sprunk <stephen@sprunk.org> - 2014-12-27 13:03 -0600
Re: solution allocation of memory and composite numbers Keith Thompson <kst-u@mib.org> - 2014-12-27 12:24 -0800
Re: solution allocation of memory and composite numbers Keith Thompson <kst-u@mib.org> - 2014-12-27 12:23 -0800
Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-27 13:31 -0800
Re: solution allocation of memory and composite numbers Öö Tiib <ootiib@hot.ee> - 2014-12-27 18:42 -0800
Re: solution allocation of memory and composite numbers Keith Thompson <kst-u@mib.org> - 2014-12-27 22:07 -0800
Re: solution allocation of memory and composite numbers raltbos@xs4all.nl (Richard Bos) - 2014-12-30 19:26 +0000
Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2014-12-30 20:01 +0000
Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-30 12:18 -0800
Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2014-12-30 21:15 +0000
Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-30 13:49 -0800
Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2014-12-30 22:03 +0000
Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2014-12-30 23:57 +0000
Re: solution allocation of memory and composite numbers BartC <bc@freeuk.com> - 2014-12-30 22:35 +0000
Re: solution allocation of memory and composite numbers Dr Nick <nospam-4@temporary-address.org.uk> - 2014-12-31 12:24 +0000
Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2014-12-31 17:08 +0000
Re: solution allocation of memory and composite numbers Dr Nick <nospam-4@temporary-address.org.uk> - 2014-12-31 17:37 +0000
Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2014-12-30 20:09 +0000
Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-30 12:24 -0800
Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2014-12-30 21:28 +0000
Re: solution allocation of memory and composite numbers Malcolm McLean <malcolm.mclean5@btinternet.com> - 2014-12-30 13:53 -0800
Re: solution allocation of memory and composite numbers Kaz Kylheku <kaz@kylheku.com> - 2015-01-04 02:22 +0000
Re: solution allocation of memory and composite numbers Xavier Roche <xroche@free.fr.NOSPAM.invalid> - 2014-12-31 13:32 +0100
Re: solution allocation of memory and composite numbers BartC <bc@freeuk.com> - 2014-12-27 01:37 +0000
Re: solution allocation of memory and composite numbers raltbos@xs4all.nl (Richard Bos) - 2014-12-27 12:19 +0000
Re: solution allocation of memory and composite numbers gazelle@shell.xmission.com (Kenny McCormack) - 2014-12-27 14:39 +0000
Re: solution allocation of memory and composite numbers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-12-24 22:29 +0000
Re: solution allocation of memory and composite numbers BartC <bc@freeuk.com> - 2014-12-24 15:05 +0000
Re: solution allocation of memory and composite numbers Richard Heathfield <invalid@see.sig.invalid> - 2014-12-24 16:55 +0000
iso646.h Noob <root@127.0.0.1> - 2014-12-25 18:26 +0100
Re: iso646.h Geoff <geoff@invalid.invalid> - 2014-12-25 18:31 -0800
Re: iso646.h Noob <root@127.0.0.1> - 2014-12-26 18:23 +0100
Re: iso646.h Keith Thompson <kst-u@mib.org> - 2014-12-25 21:31 -0800
Re: iso646.h fir <profesor.fir@gmail.com> - 2014-12-26 09:42 -0800
Re: solution allocation of memory and composite numbers Barry Schwarz <schwarzb@dqel.com> - 2014-12-24 09:06 -0800
Re: solution allocation of memory and composite numbers Richard Heathfield <invalid@see.sig.invalid> - 2014-12-24 16:59 +0000
Re: solution allocation of memory and composite numbers BartC <bc@freeuk.com> - 2014-12-24 17:26 +0000
Re: solution allocation of memory and composite numbers asetofsymbols@gmail.com - 2014-12-24 11:42 -0800
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