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Re: The difference between strtol() and strtoul() ?

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Keith Thompson <Keith.S.Thompson+u@gmail.com> writes:

> Tim Rentsch <tr.17687@z991.linuxsc.com> writes:
>> Ben Bacarisse <ben@bsb.me.uk> writes:
>> [range questions for strtol(), etc]
>>
>>> I think there /is/ something problematic with the wording about the
>>> negation.  It happens "in the return type" but how can
>>> 9223372036854775808 be negated in the type long long int?  OK, the
>>> negated value can be /represented/ in the type long long int but that's
>>> not quite the same thing.  On the othee hand, for the unsigned return
>>> types, the negation "in the return type" is what produces ULONG_MAX for
>>> "-1" when the negated value, -1, can't be /represented/ in the return
>>> type.  It's a case where, over the years, I've just got used to what's
>>> happening.
>>
>> I understand what these functions do, but their specification in the
>> C standard is a little off.  To my way of thinking the impact is
>> minimal, but the specified behavior is either unequivocally wrong or
>> there are some cases that give rise to undefined behavior.
>
> Can you give an example where the specified behavior causes undefined
> behavior?

I don't want to pre-empt Tim's answer, but the wording that bothers me
is

  "If the subject sequence begins with a minus sign, the value resulting
  from the conversion is negated (in the return type)."

For strtoll("-9223372036854775808", 0, 0) the value resulting from the
conversion is 9223372036854775808 which can not even be represented in
the return type, so how can it be negated "in the return type"?

-- 
Ben.

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The difference between strtol() and strtoul() ? gazelle@shell.xmission.com (Kenny McCormack) - 2024-06-20 14:06 +0000
  Re: The difference between strtol() and strtoul() ? scott@slp53.sl.home (Scott Lurndal) - 2024-06-20 14:46 +0000
    Re: The difference between strtol() and strtoul() ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-20 14:37 -0700
  Re: The difference between strtol() and strtoul() ? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2024-06-20 14:48 +0000
  Re: The difference between strtol() and strtoul() ? Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2024-06-20 15:26 +0000
  Re: The difference between strtol() and strtoul() ? Kaz Kylheku <643-408-1753@kylheku.com> - 2024-06-20 22:55 +0000
    Re: The difference between strtol() and strtoul() ? gazelle@shell.xmission.com (Kenny McCormack) - 2024-06-20 23:35 +0000
  Re: The difference between strtol() and strtoul() ? gazelle@shell.xmission.com (Kenny McCormack) - 2024-06-21 13:58 +0000
    Re: The difference between strtol() and strtoul() ? Michael S <already5chosen@yahoo.com> - 2024-06-21 18:28 +0300
      Re: The difference between strtol() and strtoul() ? Michael S <already5chosen@yahoo.com> - 2024-06-21 18:53 +0300
        Re: The difference between strtol() and strtoul() ? scott@slp53.sl.home (Scott Lurndal) - 2024-06-21 16:14 +0000
          Re: The difference between strtol() and strtoul() ? scott@slp53.sl.home (Scott Lurndal) - 2024-06-21 16:54 +0000
            Re: The difference between strtol() and strtoul() ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-22 06:44 +0000
              Re: The difference between strtol() and strtoul() ? scott@slp53.sl.home (Scott Lurndal) - 2024-06-22 15:16 +0000
                Re: The difference between strtol() and strtoul() ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-22 23:21 +0000
                Re: The difference between strtol() and strtoul() ? James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-06-22 20:10 -0400
        Re: The difference between strtol() and strtoul() ? Ben Bacarisse <ben@bsb.me.uk> - 2024-06-21 18:15 +0100
          Re: The difference between strtol() and strtoul() ? Michael S <already5chosen@yahoo.com> - 2024-06-23 12:19 +0300
            Re: The difference between strtol() and strtoul() ? Ben Bacarisse <ben@bsb.me.uk> - 2024-06-23 12:38 +0100
              Re: The difference between strtol() and strtoul() ? Michael S <already5chosen@yahoo.com> - 2024-06-23 15:32 +0300
                Re: The difference between strtol() and strtoul() ? Ben Bacarisse <ben@bsb.me.uk> - 2024-06-23 16:30 +0100
                Re: The difference between strtol() and strtoul() ? Michael S <already5chosen@yahoo.com> - 2024-06-23 18:47 +0300
                Re: The difference between strtol() and strtoul() ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-06-23 10:58 -0700
                Re: The difference between strtol() and strtoul() ? scott@slp53.sl.home (Scott Lurndal) - 2024-06-23 21:19 +0000
                Re: The difference between strtol() and strtoul() ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-06-23 22:28 -0700
                Re: The difference between strtol() and strtoul() ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-23 16:01 -0700
                Re: The difference between strtol() and strtoul() ? Ben Bacarisse <ben@bsb.me.uk> - 2024-06-24 00:49 +0100
                Re: The difference between strtol() and strtoul() ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-23 17:49 -0700
                Re: The difference between strtol() and strtoul() ? Kaz Kylheku <643-408-1753@kylheku.com> - 2024-06-24 02:29 +0000
                Re: The difference between strtol() and strtoul() ? Kaz Kylheku <643-408-1753@kylheku.com> - 2024-06-24 02:31 +0000
                Re: The difference between strtol() and strtoul() ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-23 20:12 -0700
                Re: The difference between strtol() and strtoul() ? Kaz Kylheku <643-408-1753@kylheku.com> - 2024-06-24 06:05 +0000
                Re: The difference between strtol() and strtoul() ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-23 20:11 -0700
                Re: The difference between strtol() and strtoul() ? Michael S <already5chosen@yahoo.com> - 2024-06-24 13:19 +0300
                Re: The difference between strtol() and strtoul() ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-06-23 22:30 -0700
                Re: The difference between strtol() and strtoul() ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-24 00:48 +0000
        Re: The difference between strtol() and strtoul() ? James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-06-21 14:38 -0400
          Re: The difference between strtol() and strtoul() ? gazelle@shell.xmission.com (Kenny McCormack) - 2024-06-21 18:43 +0000
            Re: The difference between strtol() and strtoul() ? Michael S <already5chosen@yahoo.com> - 2024-06-23 11:47 +0300
          Re: The difference between strtol() and strtoul() ? Michael S <already5chosen@yahoo.com> - 2024-06-22 21:18 +0300
      Re: The difference between strtol() and strtoul() ? Ben Bacarisse <ben@bsb.me.uk> - 2024-06-21 18:02 +0100
        Re: The difference between strtol() and strtoul() ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-21 10:38 -0700
          Re: The difference between strtol() and strtoul() ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-22 06:43 +0000
          Re: The difference between strtol() and strtoul() ? Michael S <already5chosen@yahoo.com> - 2024-06-22 21:04 +0300
            Re: The difference between strtol() and strtoul() ? Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-22 23:22 +0000
            Re: The difference between strtol() and strtoul() ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-22 16:43 -0700
    Re: The difference between strtol() and strtoul() ? Michael S <already5chosen@yahoo.com> - 2024-06-21 19:00 +0300
      Re: The difference between strtol() and strtoul() ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-21 10:50 -0700
    Re: The difference between strtol() and strtoul() ? Kaz Kylheku <643-408-1753@kylheku.com> - 2024-06-22 22:07 +0000
  Re: The difference between strtol() and strtoul() ? Richard Kettlewell <invalid@invalid.invalid> - 2024-06-23 17:39 +0100

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