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what is the output

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  what is the output vinay kumar <vinay5b9@gmail.com> - 2011-07-03 09:32 -0700
    Re: what is the output "Joachim Schmitz" <nospam.jojo@schmitz-digital.de> - 2011-07-03 19:43 +0200
    Re: what is the output Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-07-03 13:47 -0400
      Re: what is the output Keith Thompson <kst-u@mib.org> - 2011-07-03 12:15 -0700
      Re: what is the output Chad <cdalten@gmail.com> - 2011-07-03 13:55 -0700
        Re: what is the output "osmium" <r124c4u102@comcast.net> - 2011-07-03 16:20 -0500
        Re: what is the output Keith Thompson <kst-u@mib.org> - 2011-07-03 14:24 -0700
          Re: what is the output Chad <cdalten@gmail.com> - 2011-07-03 16:13 -0700
            Re: what is the output "Morris Keesan" <mkeesan@post.harvard.edu> - 2011-07-03 21:10 -0400
            Re: what is the output Keith Thompson <kst-u@mib.org> - 2011-07-04 14:22 -0700
            Re: what is the output Todd Carnes <toddcarnes@gmail.com> - 2011-07-05 03:30 +0000
        Re: what is the output John Gordon <gordon@panix.com> - 2011-07-05 02:26 +0000
      Re: what is the output Tim Rentsch <txr@alumni.caltech.edu> - 2011-07-03 18:30 -0700
        Re: what is the output Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-07-03 21:58 -0400
          Re: what is the output Tim Rentsch <txr@alumni.caltech.edu> - 2011-07-04 17:10 -0700
            Re: what is the output Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-07-04 21:42 -0400
              Re: what is the output Shao Miller <sha0.miller@gmail.com> - 2011-07-04 22:51 -0400
              Re: what is the output Tim Rentsch <txr@alumni.caltech.edu> - 2011-07-06 16:23 -0700
      Re: what is the output Michael Press <rubrum@pacbell.net> - 2011-07-03 21:23 -0700
    Re: what is the output Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-07-03 14:06 -0600
    Re: what is the output Tim Rentsch <txr@alumni.caltech.edu> - 2011-07-03 18:19 -0700
      Re: what is the output Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-07-03 22:12 -0400
        Re: what is the output Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2011-07-03 21:16 -0600
      Re: what is the output Keith Thompson <kst-u@mib.org> - 2011-07-04 13:59 -0700
        Re: what is the output Tim Rentsch <txr@alumni.caltech.edu> - 2011-07-04 17:15 -0700
    Re: what is the output Martin Ambuhl <mambuhl@earthlink.net> - 2011-07-04 17:21 -0400
      Re: what is the output Tim Rentsch <txr@alumni.caltech.edu> - 2011-07-04 17:27 -0700
        Re: what is the output Keith Thompson <kst-u@mib.org> - 2011-07-04 18:07 -0700
          Re: what is the output Tim Rentsch <txr@alumni.caltech.edu> - 2011-07-06 17:08 -0700
      Re: what is the output "Morris Keesan" <mkeesan@post.harvard.edu> - 2011-07-04 22:19 -0400
        Re: what is the output Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-07-04 23:19 -0400
          Re: what is the output Keith Thompson <kst-u@mib.org> - 2011-07-05 08:34 -0700
    Re: what is the output Shao Miller <sha0.miller@gmail.com> - 2011-07-04 18:26 -0400
      Re: what is the output Todd Carnes <toddcarnes@gmail.com> - 2011-07-05 03:36 +0000

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#7506 — what is the output

main()
{
int d=010;
printf("%d",d);
}

please give with explanation

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#7512

vinay kumar wrote:
> main()
> {
> int d=010;
> printf("%d",d);
> }
> 
> please give with explanation

What output do you get.
What output did you expect and why?

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#7513

On 7/3/2011 12:32 PM, vinay kumar wrote:
> main()
> {
> int d=010;
> printf("%d",d);
> }
>
> please give with explanation

     Undefined, because a variable-argument function is used
without a prototyped declaration.

     Also implementation-defined, because the final line of text
output is not terminated with a newline.

     Also either (1) "semi-undefined" because a C90 int-valued
function returns without returning a value, or (2) implementation-
defined because a C99 compiler must diagnose a function definition
without return type, and *if* it translates the program anyhow it
gives it an implementation-defined meaning.

     ... but the answer you're probably looking for is "8", and
the explanation will be found in the low-numbered pages of your
C textbook -- you know, that unopened volume you've been carrying
around.  Open it (it won't bite you), and see what it has to say
about "integer constants" or some similar term.

-- 
Eric Sosman
esosman@ieee-dot-org.invalid

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#7514

Eric Sosman <esosman@ieee-dot-org.invalid> writes:
> On 7/3/2011 12:32 PM, vinay kumar wrote:
>> main()
>> {
>> int d=010;
>> printf("%d",d);
>> }
>>
>> please give with explanation
>
>      Undefined, because a variable-argument function is used
> without a prototyped declaration.
>
>      Also implementation-defined, because the final line of text
> output is not terminated with a newline.
>
>      Also either (1) "semi-undefined" because a C90 int-valued
> function returns without returning a value, or (2) implementation-
> defined because a C99 compiler must diagnose a function definition
> without return type, and *if* it translates the program anyhow it
> gives it an implementation-defined meaning.

Actually, I think that the behavior of a program that violates a
constraint (given that the compiler chooses to translate it anyway)
is undefined, not implementation-defined.

[...]

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Nokia
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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#7522

On Jul 3, 10:47 am, Eric Sosman <esos...@ieee-dot-org.invalid> wrote:
> On 7/3/2011 12:32 PM, vinay kumar wrote:
>
> > main()
> > {
> > int d=010;
> > printf("%d",d);
> > }
>
> > please give with explanation
>
>      Undefined, because a variable-argument function is used
> without a prototyped declaration.
>
>      Also implementation-defined, because the final line of text
> output is not terminated with a newline.
>
>      Also either (1) "semi-undefined" because a C90 int-valued
> function returns without returning a value, or (2) implementation-
> defined because a C99 compiler must diagnose a function definition
> without return type, and *if* it translates the program anyhow it
> gives it an implementation-defined meaning.
>
>      ... but the answer you're probably looking for is "8", and
> the explanation will be found in the low-numbered pages of your
> C textbook -- you know, that unopened volume you've been carrying
> around.  Open it (it won't bite you), and see what it has to say
> about "integer constants" or some similar term.
>

I know I shouldn't do this, but I'm going to take the bait on this
one. How do you figure the output is the "8".

Chad

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#7525

"Chad" wrote:

On Jul 3, 10:47 am, Eric Sosman <esos...@ieee-dot-org.invalid> wrote:
> On 7/3/2011 12:32 PM, vinay kumar wrote:
>
> > main()
> > {
> > int d=010;
> > printf("%d",d);
> > }
>
> > please give with explanation
>
> Undefined, because a variable-argument function is used
> without a prototyped declaration.
>
> Also implementation-defined, because the final line of text
> output is not terminated with a newline.
>
> Also either (1) "semi-undefined" because a C90 int-valued
> function returns without returning a value, or (2) implementation-
> defined because a C99 compiler must diagnose a function definition
> without return type, and *if* it translates the program anyhow it
> gives it an implementation-defined meaning.
>
> ... but the answer you're probably looking for is "8", and
> the explanation will be found in the low-numbered pages of your
> C textbook -- you know, that unopened volume you've been carrying
> around. Open it (it won't bite you), and see what it has to say
> about "integer constants" or some similar term.
>

I know I shouldn't do this, but I'm going to take the bait on this
one. How do you figure the output is the "8".

1x8^1 + 0x8^0 = 8 

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#7527

Chad <cdalten@gmail.com> writes:
> On Jul 3, 10:47 am, Eric Sosman <esos...@ieee-dot-org.invalid> wrote:
>> On 7/3/2011 12:32 PM, vinay kumar wrote:
>>
>> > main()
>> > {
>> > int d=010;
>> > printf("%d",d);
>> > }
>>
>> > please give with explanation
>>
>>      Undefined, because a variable-argument function is used
>> without a prototyped declaration.
>>
>>      Also implementation-defined, because the final line of text
>> output is not terminated with a newline.
>>
>>      Also either (1) "semi-undefined" because a C90 int-valued
>> function returns without returning a value, or (2) implementation-
>> defined because a C99 compiler must diagnose a function definition
>> without return type, and *if* it translates the program anyhow it
>> gives it an implementation-defined meaning.
>>
>>      ... but the answer you're probably looking for is "8", and
>> the explanation will be found in the low-numbered pages of your
>> C textbook -- you know, that unopened volume you've been carrying
>> around.  Open it (it won't bite you), and see what it has to say
>> about "integer constants" or some similar term.
>
> I know I shouldn't do this, but I'm going to take the bait on this
> one. How do you figure the output is the "8".

Did you try running the program?  What output did you get?

Eric already explained how to find the explanation: see what your C
textbook (or on-line tutorial, or copy of the standard) says about
integer constants.

If you're not interested in doing that, I can explain exactly
why the output is what it is, but you'd learn more by doing your
own research.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Nokia
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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#7537

On Jul 3, 2:24 pm, Keith Thompson <ks...@mib.org> wrote:
> Chad <cdal...@gmail.com> writes:
> > On Jul 3, 10:47 am, Eric Sosman <esos...@ieee-dot-org.invalid> wrote:
> >> On 7/3/2011 12:32 PM, vinay kumar wrote:
>
> >> > main()
> >> > {
> >> > int d=010;
> >> > printf("%d",d);
> >> > }
>
> >> > please give with explanation
>
> >>      Undefined, because a variable-argument function is used
> >> without a prototyped declaration.
>
> >>      Also implementation-defined, because the final line of text
> >> output is not terminated with a newline.
>
> >>      Also either (1) "semi-undefined" because a C90 int-valued
> >> function returns without returning a value, or (2) implementation-
> >> defined because a C99 compiler must diagnose a function definition
> >> without return type, and *if* it translates the program anyhow it
> >> gives it an implementation-defined meaning.
>
> >>      ... but the answer you're probably looking for is "8", and
> >> the explanation will be found in the low-numbered pages of your
> >> C textbook -- you know, that unopened volume you've been carrying
> >> around.  Open it (it won't bite you), and see what it has to say
> >> about "integer constants" or some similar term.
>
> > I know I shouldn't do this, but I'm going to take the bait on this
> > one. How do you figure the output is the "8".
>
> Did you try running the program?  What output did you get?
>
> Eric already explained how to find the explanation: see what your C
> textbook (or on-line tutorial, or copy of the standard) says about
> integer constants.
>

I got the number "8" after I compiled and ran this code on my Linux
box here at home. I just wasn't clear on why the computer produced the
number "8" and not the number "10".

Chad

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#7546

On Sun, 03 Jul 2011 19:13:06 -0400, Chad <cdalten@gmail.com> wrote:

> On Jul 3, 2:24 pm, Keith Thompson <ks...@mib.org> wrote:
>> Chad <cdal...@gmail.com> writes:
>> > On Jul 3, 10:47 am, Eric Sosman <esos...@ieee-dot-org.invalid> wrote:
>> >> On 7/3/2011 12:32 PM, vinay kumar wrote:
>>
>> >> > main()
>> >> > {
>> >> > int d=010;
>> >> > printf("%d",d);
>> >> > }
...
> I got the number "8" after I compiled and ran this code on my Linux
> box here at home. I just wasn't clear on why the computer produced the
> number "8" and not the number "10".

010 != 10

As someone else suggested, go read what any C reference has to say
about integer constants.  Or just google for "C integer constant", and
see what the first result tells you.


-- 
Morris Keesan -- mkeesan@post.harvard.edu

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#7608

Chad <cdalten@gmail.com> writes:
> On Jul 3, 2:24 pm, Keith Thompson <ks...@mib.org> wrote:
>> Chad <cdal...@gmail.com> writes:
>> > On Jul 3, 10:47 am, Eric Sosman <esos...@ieee-dot-org.invalid> wrote:
>> >> On 7/3/2011 12:32 PM, vinay kumar wrote:
>>
>> >> > main()
>> >> > {
>> >> > int d=010;
>> >> > printf("%d",d);
>> >> > }
>>
>> >> > please give with explanation
>>
>> >>      Undefined, because a variable-argument function is used
>> >> without a prototyped declaration.
>>
>> >>      Also implementation-defined, because the final line of text
>> >> output is not terminated with a newline.
>>
>> >>      Also either (1) "semi-undefined" because a C90 int-valued
>> >> function returns without returning a value, or (2) implementation-
>> >> defined because a C99 compiler must diagnose a function definition
>> >> without return type, and *if* it translates the program anyhow it
>> >> gives it an implementation-defined meaning.
>>
>> >>      ... but the answer you're probably looking for is "8", and
>> >> the explanation will be found in the low-numbered pages of your
>> >> C textbook -- you know, that unopened volume you've been carrying
>> >> around.  Open it (it won't bite you), and see what it has to say
>> >> about "integer constants" or some similar term.
>>
>> > I know I shouldn't do this, but I'm going to take the bait on this
>> > one. How do you figure the output is the "8".
>>
>> Did you try running the program?  What output did you get?
>>
>> Eric already explained how to find the explanation: see what your C
>> textbook (or on-line tutorial, or copy of the standard) says about
>> integer constants.
>
> I got the number "8" after I compiled and ran this code on my Linux
> box here at home. I just wasn't clear on why the computer produced the
> number "8" and not the number "10".

That's probably because you ignored the advice several people have
given, to consult your C reference and see what it has to say about
integer constants.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Nokia
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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#7634

On Sun, 03 Jul 2011 16:13:06 -0700, Chad wrote:

> On Jul 3, 2:24 pm, Keith Thompson <ks...@mib.org> wrote:
>> Chad <cdal...@gmail.com> writes:
>> > On Jul 3, 10:47 am, Eric Sosman <esos...@ieee-dot-org.invalid> wrote:
>> >> On 7/3/2011 12:32 PM, vinay kumar wrote:
>>
>> >> > main()
>> >> > {
>> >> > int d=010;
>> >> > printf("%d",d);
>> >> > }
>>
>> >> > please give with explanation
>>

[snip]

> I got the number "8" after I compiled and ran this code on my Linux box
> here at home. I just wasn't clear on why the computer produced the
> number "8" and not the number "10".
> 
> Chad

Someone already told you that a leading zero is used to indicate that you 
are using the octal numbering system vice, the decimal system, correct?

What does the octal number 010 equal in the decimal system?

Hint: 010 in the binary system is equal to 2 in the decimal system.

Todd

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#7628

In <bfa37ea9-d7cd-457b-8f28-070a945a8da6@p10g2000prf.googlegroups.com> Chad <cdalten@gmail.com> writes:

> > > int d=010;

> I know I shouldn't do this, but I'm going to take the bait on this
> one. How do you figure the output is the "8".

Because a leading zero indicates octal notation instead of decimal.

-- 
John Gordon                   A is for Amy, who fell down the stairs
gordon@panix.com              B is for Basil, assaulted by bears
                                -- Edward Gorey, "The Gashlycrumb Tinies"

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#7549

Eric Sosman <esosman@ieee-dot-org.invalid> writes:

> On 7/3/2011 12:32 PM, vinay kumar wrote:
>> main()
>> {
>> int d=010;
>> printf("%d",d);
>> }
>>
>> please give with explanation
>[snip]
>
>     Also either (1) "semi-undefined" because a C90 int-valued
> function returns without returning a value, [snip]

Actually this aspect's behavior is defined;  only the termination
status returned to the host environment is undefined.  (Or it is
implementation-defined in a freestanding implementation.)

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#7552

On 7/3/2011 9:30 PM, Tim Rentsch wrote:
> Eric Sosman<esosman@ieee-dot-org.invalid>  writes:
>
>> On 7/3/2011 12:32 PM, vinay kumar wrote:
>>> main()
>>> {
>>> int d=010;
>>> printf("%d",d);
>>> }
>>>
>>> please give with explanation
>> [snip]
>>
>>      Also either (1) "semi-undefined" because a C90 int-valued
>> function returns without returning a value, [snip]
>
> Actually this aspect's behavior is defined;  only the termination
> status returned to the host environment is undefined.  (Or it is
> implementation-defined in a freestanding implementation.)

     To the first point, that's what I intended to indicate with the
weasel-words "semi-defined."  The behavior is undefined if (1) the
caller of main() is written in C, and (2) the caller makes use of the
returned value.  If the returned value is not used, there's no problem.
And if the caller is not written in C, then C's rules don't apply.

     To the second point, in a free-standing implementation it is not
possible to predict (from the information given) what output, if any,
is produced.  For all we know, printf() computes checksums of its
arguments, combines them into a complex number, and returns the
logarithm thereof after launching the nuclear missiles.

-- 
Eric Sosman
esosman@ieee-dot-org.invalid

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#7619

Eric Sosman <esosman@ieee-dot-org.invalid> writes:

> On 7/3/2011 9:30 PM, Tim Rentsch wrote:
>> Eric Sosman<esosman@ieee-dot-org.invalid>  writes:
>>
>>> On 7/3/2011 12:32 PM, vinay kumar wrote:
>>>> main()
>>>> {
>>>> int d=010;
>>>> printf("%d",d);
>>>> }
>>>>
>>>> please give with explanation
>>> [snip]
>>>
>>>      Also either (1) "semi-undefined" because a C90 int-valued
>>> function returns without returning a value, [snip]
>>
>> Actually this aspect's behavior is defined;  only the termination
>> status returned to the host environment is undefined.  (Or it is
>> implementation-defined in a freestanding implementation.)
>
>     To the first point, that's what I intended to indicate with the
> weasel-words "semi-defined."  The behavior is undefined if (1) the
> caller of main() is written in C, and (2) the caller makes use of the
> returned value.  If the returned value is not used, there's no problem.
> And if the caller is not written in C, then C's rules don't apply.

Reading this reminds me of a quote: "I concede your point -
if things were different, they wouldn't be the same."

Yes, _if_ it were true that what we're looking at is only
part of a program rather than the whole program then these
considerations might come into play.  For all we know this
piece comes after an #if 0 ...

However, most who commented on it, including yourself,
responded as though what's presented is an entire program.

In that context, C90 specifically and explicitly defines the
behavior of returning from main() without giving a return
value to say the termination status returned to the host
environment is undefined.  Anything beyond that is simply
outside the scope of the C standard, as is true for all
terminations.  You might as well say that 'return 0;' from
main() is "semi-defined";  in neither case is there anything
more to say about what happens further, as whatever that may
be is outside the realm of both language and implementation.


>     To the second point, in a free-standing implementation it is not
> possible to predict (from the information given) what output, if any,
> is produced.  For all we know, printf() computes checksums of its
> arguments, combines them into a complex number, and returns the
> logarithm thereof after launching the nuclear missiles.

Sorry, I thought it was clear from how the snipping was done
that I was addressing only the one aspect of the program
that the sentence being responded to concerns itself with,
namely, the behavor of returning without using a 'return'
statement.

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#7625

On 7/4/2011 8:10 PM, Tim Rentsch wrote:
> [...]
> Reading this reminds me of a quote: "I concede your point -
> if things were different, they wouldn't be the same."

     Ass.

-- 
Eric Sosman
esosman@ieee-dot-org.invalid

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#7631

On Mon, 04 Jul 2011 21:42:34 -0400, Eric Sosman 
<esosman@ieee-dot-org.invalid> wrote:
> On 7/4/2011 8:10 PM, Tim Rentsch wrote:
> > [...]
> > Reading this reminds me of a quote: "I concede your point -
> > if things were different, they wouldn't be the same."


>      Ass.

Some day I'd like to throw a comp.lang.c party.  Even the 
10-errors-in-5-lines-of-code-no-follow-up-post entities could find 
themselves as welcome guests.  Then we could all share merry laughter 
and memories.  See you all there!

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#7794

Eric Sosman <esosman@ieee-dot-org.invalid> writes:

> On 7/4/2011 8:10 PM, Tim Rentsch wrote:
>> [...]
>> Reading this reminds me of a quote: "I concede your point -
>> if things were different, they wouldn't be the same."
>
>     Ass.

You gave a bogus argument, made in an effort to support a
position that is clearly technically wrong.  If you want to
make bogus arguments, that's up to you, but if you do you
shouldn't be surprised or outraged to get a response calling
attention to that fact.

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#7560

In article <iuqa1r$soe$1@dont-email.me>,
 Eric Sosman <esosman@ieee-dot-org.invalid> wrote:

> On 7/3/2011 12:32 PM, vinay kumar wrote:
> > main()
> > {
> > int d=010;
> > printf("%d",d);
> > }
> >
> > please give with explanation
> 
>      Undefined, because a variable-argument function is used
> without a prototyped declaration.
> 
>      Also implementation-defined, because the final line of text
> output is not terminated with a newline.
> 
>      Also either (1) "semi-undefined" because a C90 int-valued
> function returns without returning a value, or (2) implementation-
> defined because a C99 compiler must diagnose a function definition
> without return type, and *if* it translates the program anyhow it
> gives it an implementation-defined meaning.
> 
>      ... but the answer you're probably looking for is "8", and
> the explanation will be found in the low-numbered pages of your
> C textbook -- you know, that unopened volume you've been carrying
> around.  Open it (it won't bite you), and see what it has to say
> about "integer constants" or some similar term.

I've had some nasty paper cuts from text books.

-- 
Michael Press

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#7519

vinay kumar <vinay5b9@gmail.com> writes:

> main()
> {
> int d=010;
> printf("%d",d);
> }
>
> please give with explanation

Please give with question?

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