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0x0F700000

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  0x0F700000 bob <bob@coolfone.comze.com> - 2012-05-07 06:40 -0700
    Re: 0x0F700000 Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-05-07 10:52 -0700
      Re: 0x0F700000 free@securityaudit.val.newsbank.net (Dick Wesseling) - 2012-05-07 20:54 +0000
        Re: 0x0F700000 Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-05-07 14:08 -0700
          Re: 0x0F700000 Robert Wessel <robertwessel2@yahoo.com> - 2012-05-08 00:22 -0500
            Re: 0x0F700000 Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-05-08 11:22 -0700
              Re: 0x0F700000 Robert Wessel <robertwessel2@yahoo.com> - 2012-05-08 15:24 -0500
    Re: 0x0F700000 Willem <willem@toad.stack.nl> - 2012-05-07 18:05 +0000

#1547 — 0x0F700000

Is there something special about the value 0x0F700000 in programming?  I vaguely remember that programmers might set their uninitialized stuff to that, but I'm not sure.

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#1548

On 5/7/12 6:40 AM, bob wrote:
> Is there something special about the value 0x0F700000 in programming?  I vaguely remember that programmers might set their uninitialized stuff to that, but I'm not sure.
A google search for 0x0F700000 doesn't turn up anything immediately 
apparent.

It almost looks like a specific x86 instruction, but that doesn't 
exactly pan out either:

http://ref.x86asm.net/geek.html#x0F70

It might just be a magic number that someone decided, so that they could 
detect uninitialized values. Other than that, I don't see anything 
useful about that specific value.

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#1551

In article <kZTpr.80027$YM2.56448@newsfe05.iad>,
	Daniel Pitts <newsgroup.nospam@virtualinfinity.net> writes:
> On 5/7/12 6:40 AM, bob wrote:
>> Is there something special about the value 0x0F700000 in programming?  I vaguely remember that programmers might set their uninitialized stuff to that, but I'm not sure.
> A google search for 0x0F700000 doesn't turn up anything immediately 
> apparent.
> 
> It almost looks like a specific x86 instruction, but that doesn't 
> exactly pan out either:
> 

F700 is an 68000 instruction "unimp". An attempt to execute this
data will give a trap on that CPU.

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#1552

On 5/7/12 1:54 PM, Dick Wesseling wrote:
> In article<kZTpr.80027$YM2.56448@newsfe05.iad>,
> 	Daniel Pitts<newsgroup.nospam@virtualinfinity.net>  writes:
>> On 5/7/12 6:40 AM, bob wrote:
>>> Is there something special about the value 0x0F700000 in programming?  I vaguely remember that programmers might set their uninitialized stuff to that, but I'm not sure.
>> A google search for 0x0F700000 doesn't turn up anything immediately
>> apparent.
>>
>> It almost looks like a specific x86 instruction, but that doesn't
>> exactly pan out either:
>>
>
> F700 is an 68000 instruction "unimp". An attempt to execute this
> data will give a trap on that CPU.
That seems a plausible reason, but that doesn't align with 0F 70 00 00, 
unless the OP has miscounted zeros.

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#1556

On Mon, 07 May 2012 14:08:11 -0700, Daniel Pitts
<newsgroup.nospam@virtualinfinity.net> wrote:

>On 5/7/12 1:54 PM, Dick Wesseling wrote:
>> In article<kZTpr.80027$YM2.56448@newsfe05.iad>,
>> 	Daniel Pitts<newsgroup.nospam@virtualinfinity.net>  writes:
>>> On 5/7/12 6:40 AM, bob wrote:
>>>> Is there something special about the value 0x0F700000 in programming?  I vaguely remember that programmers might set their uninitialized stuff to that, but I'm not sure.
>>> A google search for 0x0F700000 doesn't turn up anything immediately
>>> apparent.
>>>
>>> It almost looks like a specific x86 instruction, but that doesn't
>>> exactly pan out either:
>>>
>>
>> F700 is an 68000 instruction "unimp". An attempt to execute this
>> data will give a trap on that CPU.
>That seems a plausible reason, but that doesn't align with 0F 70 00 00, 
>unless the OP has miscounted zeros.


68K is big endian.

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#1561

On 5/7/12 10:22 PM, Robert Wessel wrote:
> On Mon, 07 May 2012 14:08:11 -0700, Daniel Pitts
> <newsgroup.nospam@virtualinfinity.net>  wrote:
>
>> On 5/7/12 1:54 PM, Dick Wesseling wrote:
>>> In article<kZTpr.80027$YM2.56448@newsfe05.iad>,
>>> 	Daniel Pitts<newsgroup.nospam@virtualinfinity.net>   writes:
>>>> On 5/7/12 6:40 AM, bob wrote:
>>>>> Is there something special about the value 0x0F700000 in programming?  I vaguely remember that programmers might set their uninitialized stuff to that, but I'm not sure.
>>>> A google search for 0x0F700000 doesn't turn up anything immediately
>>>> apparent.
>>>>
>>>> It almost looks like a specific x86 instruction, but that doesn't
>>>> exactly pan out either:
>>>>
>>>
>>> F700 is an 68000 instruction "unimp". An attempt to execute this
>>> data will give a trap on that CPU.
>> That seems a plausible reason, but that doesn't align with 0F 70 00 00,
>> unless the OP has miscounted zeros.
>
>
> 68K is big endian.

And? f7 00 is different than 0f 70, regardless of endianess.

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#1562

On Tue, 08 May 2012 11:22:49 -0700, Daniel Pitts
<newsgroup.nospam@virtualinfinity.net> wrote:

>On 5/7/12 10:22 PM, Robert Wessel wrote:
>> On Mon, 07 May 2012 14:08:11 -0700, Daniel Pitts
>> <newsgroup.nospam@virtualinfinity.net>  wrote:
>>
>>> On 5/7/12 1:54 PM, Dick Wesseling wrote:
>>>> In article<kZTpr.80027$YM2.56448@newsfe05.iad>,
>>>> 	Daniel Pitts<newsgroup.nospam@virtualinfinity.net>   writes:
>>>>> On 5/7/12 6:40 AM, bob wrote:
>>>>>> Is there something special about the value 0x0F700000 in programming?  I vaguely remember that programmers might set their uninitialized stuff to that, but I'm not sure.
>>>>> A google search for 0x0F700000 doesn't turn up anything immediately
>>>>> apparent.
>>>>>
>>>>> It almost looks like a specific x86 instruction, but that doesn't
>>>>> exactly pan out either:
>>>>>
>>>>
>>>> F700 is an 68000 instruction "unimp". An attempt to execute this
>>>> data will give a trap on that CPU.
>>> That seems a plausible reason, but that doesn't align with 0F 70 00 00,
>>> unless the OP has miscounted zeros.
>>
>>
>> 68K is big endian.
>
>And? f7 00 is different than 0f 70, regardless of endianess.


Definite brainfart from me there...

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#1549

bob wrote:
) Is there something special about the value 0x0F700000 in programming?  I
) vaguely remember that programmers might set their uninitialized stuff to
) that, but I'm not sure.

No, the canonical value for uninitialized is 0xDEADBEEF


SaSW, Willem
-- 
Disclaimer: I am in no way responsible for any of the statements
            made in the above text. For all I know I might be
            drugged or something..
            No I'm not paranoid. You all think I'm paranoid, don't you !
#EOT

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