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| From | Keith Thompson <kst-u@mib.org> |
| Newsgroups | comp.lang.c |
| Subject | Re: better atoi |
| Date | Fri, 10 Feb 2017 15:16:25 -0800 |
| Organization | None to speak of |
| Lines | 35 |
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Joe Pfeiffer <pfeiffer@cs.nmsu.edu> writes:
> fir <profesor.fir@gmail.com> writes:
>> http://www.cplusplus.com/reference/cstdlib/strtol/
>>
>> it is said that strtol sets errno to ERANGE but is
>> not mentioned with wrong value, so im not sure if
>> it can be uniformly checked (probably yest though
>> but only not noted (i not checked it though))
>
> It says it returns LONG_MAX or LONG_MIN in this case (so it appears it
> is possible that if the string does in fact represent one of those
> values, you can't reliably detect the conversion was successful -- as
> we've seen in other places, we can't rely on ERRNO being 0 on success.
> We'd sort of hope for it in this function...).
No, if you set errno to 0 before calling strtol() you can rely in it not
being set to ERANGE unless there's an error.
N1570 7.5p3:
The value of errno may be set to nonzero by a library function
call whether or not there is an error, provided the use of
errno is not documented in the description of the function in
this International Standard.
Since the use of errno *is* documented for strtol(), it can't set it to
nonzero unless there's an error. (I suppose you could interpret that
wording in a way that allows to set errno even if it's successful, but
that's not a reasonable reading.)
--
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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better atoi fir <profesor.fir@gmail.com> - 2017-02-10 12:24 -0800
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-10 12:35 -0800
Re: better atoi Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-02-10 14:48 -0700
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-10 14:12 -0800
Re: better atoi Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-02-10 22:36 -0700
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-11 01:07 -0800
Re: better atoi Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-02-11 10:10 -0700
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-11 09:26 -0800
Re: better atoi Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-02-11 15:36 -0700
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-12 00:18 -0800
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-12 00:31 -0800
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-12 03:47 -0800
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-12 04:22 -0800
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-12 06:08 -0800
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-12 06:13 -0800
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-12 07:31 -0800
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-12 08:02 -0800
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-12 08:08 -0800
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-12 08:17 -0800
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-12 08:23 -0800
Re: better atoi Robert Latest <boblatest@yahoo.com> - 2017-02-19 11:11 +0000
Re: better atoi Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-11 17:33 +0000
Re: better atoi Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-02-11 15:35 -0700
Re: better atoi "James R. Kuyper" <jameskuyper@verizon.net> - 2017-02-11 17:52 -0500
Re: better atoi Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-02-11 18:53 -0700
Re: better atoi Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-10 22:50 +0000
Re: better atoi Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-02-10 21:59 -0700
Re: better atoi Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-11 12:08 +0000
Re: better atoi Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-02-11 09:39 -0700
Re: better atoi Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-11 17:26 +0000
Re: better atoi Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-02-11 15:30 -0700
Re: better atoi Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-11 22:58 +0000
Re: better atoi Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-02-11 18:48 -0700
Re: better atoi Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-12 02:16 +0000
Re: better atoi "James R. Kuyper" <jameskuyper@verizon.net> - 2017-02-12 09:57 -0500
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-12 07:27 -0800
Re: better atoi jameskuyper@verizon.net - 2017-02-12 08:44 -0800
Re: better atoi fir <profesor.fir@gmail.com> - 2017-02-12 09:15 -0800
Re: better atoi Malcolm McLean <malcolm.mclean5@btinternet.com> - 2017-02-12 09:44 -0800
Re: better atoi BartC <bc@freeuk.com> - 2017-02-12 18:32 +0000
Re: better atoi Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-12 18:56 +0000
Re: better atoi BartC <bc@freeuk.com> - 2017-02-12 19:18 +0000
Re: better atoi Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-13 00:16 +0000
Re: better atoi BartC <bc@freeuk.com> - 2017-02-13 01:56 +0000
Re: better atoi Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-13 10:44 +0000
Re: better atoi BartC <bc@freeuk.com> - 2017-02-13 11:38 +0000
Re: better atoi Ben Bacarisse <ben.usenet@bsb.me.uk> - 2017-02-13 14:37 +0000
Re: better atoi BartC <bc@freeuk.com> - 2017-02-13 15:00 +0000
Re: better atoi Keith Thompson <kst-u@mib.org> - 2017-02-12 11:15 -0800
Re: better atoi BartC <bc@freeuk.com> - 2017-02-12 19:25 +0000
Re: better atoi Keith Thompson <kst-u@mib.org> - 2017-02-12 11:54 -0800
Re: better atoi supercat@casperkitty.com - 2017-02-12 13:13 -0800
Re: better atoi Keith Thompson <kst-u@mib.org> - 2017-02-10 15:16 -0800
Re: better atoi Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-02-10 22:01 -0700
Re: better atoi Keith Thompson <kst-u@mib.org> - 2017-02-11 01:30 -0800
Re: better atoi Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-02-10 22:26 -0700
Re: better atoi Nick Bowler <nbowler@draconx.ca> - 2017-02-11 00:26 +0000
Re: better atoi Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2017-02-10 22:32 -0700
Re: better atoi "James R. Kuyper" <jameskuyper@verizon.net> - 2017-02-19 11:10 -0500
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