OpenEuphoria

2. Re: Problem with copying text to the Windows clipboard

• Posted by gbonvehi Mar 20, 2009
• 1031 views

Hi Robert,
I've downloaded your program and tried to reproduce the bug but couldn't do it. Do you have a detailed way to reproduce it?

Cheers,
Guillermo

4. Re: Problem with copying text to the Windows clipboard

• Posted by RobertS Mar 21, 2009
• 1082 views

Yes, I have used -con

This is an example of getting a wrong result:

copyall 
 
27 1.28 * 
= 34.56 
 
30 % 
= 10.368 
 
6 1.28 * 2 rd 
= 7.68 
 
34.56 10.37 - 7.68 + 
= 48.38 (this is wrong) 
 
34.56 10.37 - 7.68 + 
= 31.87 (the same calculation, now it is correct) 
 
and now some random input, until it crashes: 
 
1 rd 
 
61.28 + 61.28 - 
 
173.27 28.999 * 61.28 - 
 
2 rd 
 
34.56 10.37 - 7.68 + 
 
235.78 246.77 31.004 33.889 sum 
 
52328.22 7474 + 22 - sqrt 2 rd 30 % 
 
27 1.28 * 
 
30 % 
 
6 1.28 * 2 rd 
 
34.56 10.37 - 7.68 + 
 
and now the crash: 
 
C:\EUPHORIA\include\get.e:135 in function get_number()  
A machine-level exception occurred during execution of this statement  
    <no-name> = 1 
    <no-name> = <no value> 
    <no-name> = 3 
    <no-name> = <no value> 
    <no-name> = 7.6 
    <no-name> = 100'd' 
    <no-name> = <no value> 
    <no-name> = <no value> 
 
... called from C:\EUPHORIA\include\get.e:240 in function Get()   
    <no-name> = <no value> 
    <no-name> = <no value> 
 
... called from C:\EUPHORIA\include\get.e:302 in function value()   
    <no-name> = {55'7',46'.',54'6',56'8',57'9'} 
 
... called from .\hy-lib.e:280 in function isindeednumber()   
    <no-name> = {55'7',46'.',54'6',56'8'} 
    <no-name> = {0,7.68} 
    <no-name> = 7.68 
 
... called from .\hy-calc.e:12 in procedure makenumeric()   
    <no-name> = {55'7',46'.',54'6',56'8'} 
    <no-name> = {0,7.68} 
    <no-name> = <no value> 
    <no-name> = 4 
    <no-name> = <no value> 
    <no-name> = <no value> 
 
... called from hy.exw:108 in procedure processline()   
    <no-name> = <no value> 
    <no-name> = 0 
    <no-name> = <no value> 
 
... called from hy.exw:1  

I was wrong in one regard: Meanwhile I've experienced a crash with running it from the interpreter, too.

BTW, I use a shortened and slightly modified version of conclip, but I've tested it with the original, with the same result.

I'm still open to the possibility that it can be a logical bug in my program after all, of course.

So, my main question: is it indeed conceivable, that the clipboard routine corrupts data in memory? And is there a way to find out whether it does?

Thank you for all your efforts!

Robert

6. Re: Problem with copying text to the Windows clipboard

• Posted by mattlewis (admin) Mar 21, 2009
• 975 views

Actually, they both ultimately use the same allocation function on windows. The difference is that 3.1 also caches the memory internally, in an attempt to speed up allocation and freeing memory. In effect, this duplicates the work of the OS. In the early days, this method was much faster, but as operating systems have matured, the difference has disappeared or shrunk.

There are other issues, where older versions of windows do not guarantee 8-byte aligned allocations (Win2K+ does, IIRC, as well as modern linuxes and bsds). This is critical for euphoria objects, and the internal memory handling has some workarounds to be able to properly allocate and free memory when the OS does not guarantee this.

Also, the clip board requires memory to be allocated in a special way, using GlobalAlloc, which I believe Greg's library uses. I haven't looked at the code in question, though, so I can't say where the problem might be (and I'm not on windows now, so I can't test it).

Matt

8. Re: Problem with copying text to the Windows clipboard

• Posted by jacques Mar 21, 2009
• 1024 views

This wrong, I should have checked before writing. http://msdn.microsoft.com/en-us/library/aa366596(VS.85).aspx