Why do i get "thread death" error in JessDE? - jess

i have a question about jessde. i'm using jess71p2 and eclipse juno with jessde
plugin installed. i have a jess program (see below) which works at the jess
command prompt. the jess doc says,
"Run and Debug commands for Jess programs
You can run or debug a Jess program using the normal Eclipse "Run..." menu or by
right clicking on Navigator items or in the edit window."
when i try to use the eclipse run command, i get a failure caused by "thread
death". i have setup a run configuration but still nothing.
any help would be appreciated.
duetto
(deftemplate person
(slot name)
(slot height))
(deffacts people
(person (name Joe) (height 66))
(person (name Jeff) (height 74))
(person (name Janet) (height 62)))
(defrule tallest
(person (name ?name) (height ?h))
(not (person (name ~?name) (height ?ho&:(> ?ho ?h))))
=>
(printout t ?name " is the tallest." crlf))
(reset)
(run)

Unfortunately that’s how the old time-limited downloads “expire”. Nothing you can do about it at the moment, I’m afraid. Working on getting permission to release all of Jess as open source.

Related

i don´t know why this example of the jess rule manual doesn´t work

I am reading the jess manual, exactly in 6.12. The 'test' conditional element. I copied exactly the example for try running this code, but didn´t work at all.
NOTE: I have run another examples and work fine.
(deftemplate person (slot age))
(defrule example-8
(test (eq 4 (+ 2 2)))
=>
(printout t "2 + 2 is 4!" crlf))
My result is nothing.. don´t show me any message, don´t return any error message. I really want to understand it. Please help me on this.
Many rules — and this is one — require the “initial-fact” asserted by “reset” to operate. The manual explains in more detail, but just as a best practice, you generally need to call (reset) before asserting any facts and calling (run).

Win 8.1 App crashes on user device - How to debug?

last week I published my first Windows 8.1 app on the Windows Store. So far everything works fine but now two user reported that the app crashes immediately when being launched.
Additionally I discovered that there is a CrashDump listed in the Reports/Quality section of the Dashboard. I dowloaded the CrashDump and tried to find the source of the problem using WinDbg by following this instruction: http://blogs.msdn.com/b/ntdebugging/archive/2014/01/13/debugging-a-windows-8-1-store-app-crash-dump.aspx
I was able to follow the instruction almost up to the end but then the sos library is not found:
0:006> .sympath SRV*C:\Symbols*http://msdl.microsoft.com/download/symbols
...
0:006> .exr -1
ExceptionAddress: 769eb1d7 (combase+0x000fb1d7)
ExceptionCode: c000027b
ExceptionFlags: 00000001
NumberParameters: 2
Parameter[0]: 03f3f32c
Parameter[1]: 00000001
0:006> !error c000027b
Error code: (NTSTATUS) 0xc000027b (3221226107) - Anwendungsinterne Ausnahme.
0:006> .ecxr
eax=03f3f030 ebx=00000000 ecx=00000000 edx=00000000
esi=03f3f360 edi=03f3f030 eip=769eb01f esp=03f3f314
ebp=03f3f3bc iopl=0 nv up ei pl nz ac po nc cs=001b
ss=0023 ds=0023 es=0023 fs=003b gs=0000 efl=00000212
combase+0xfb01f: 769eb01f 6a03 push 3
0:006> knL
*** Stack trace for last set context - .thread/.cxr resets it
...
0:006> dt 03f3f32c combase!_STOWED_EXCEPTION_INFORMATION_HEADER*
0x05f182e4
+0x000 Size : 0x28
+0x004 Signature : 0x53453032
0:006> .formats 0x53453032
Evaluate expression:
Hex: 53453032
Decimal: 1397043250
Octal: 12321230062
Binary: 01010011 01000101 00110000 00110010
Chars: SE02
Time: Wed Apr 09 13:34:10 2014
Float: low 8.46917e+011 high 0
Double: 6.90231e-315
0:006> dt -a1 03f3f32c combase!_STOWED_EXCEPTION_INFORMATION_V2*
[0] # 03f3f32
---------------------------------------------
0x05f182e4
+0x000 Header : _STOWED_EXCEPTION_INFORMATION_HEADER
+0x008 ResultCode : 80131500
+0x00c ExceptionForm : 0y01
+0x00c ThreadId : 0y000000000000000000010001100101 (0x465)
+0x010 ExceptionAddress : 0x76943bff Void
+0x014 StackTraceWordSize : 4
+0x018 StackTraceWords : 0xa
+0x01c StackTrace : 0x04c6c010 Void
+0x010 ErrorText : 0x76943bff "趍ﯰ???" +0x
+0x020 NestedExceptionType : 0x314f454c
+0x024 NestedException : 0x05f1be44 Void
0:006> !error 80131500
Error code: (HRESULT) 0x80131500 (2148734208) - <Unable to get error code text>
0:006> dpS 0x04c6c010 La 7697a9f1 combase!RoOriginateLanguageException+0x3b [d:\blue_gdr\com\combase\winrt\error\error.cpp # 1083]
63da3bc6 mscorlib_ni+0x9b3bc6
63e41976 mscorlib_ni+0xa51976
63e415c1 mscorlib_ni+0xa515c1
5b72f9df System_Runtime_WindowsRuntime_ni+0x1f9df
5b72f965 System_Runtime_WindowsRuntime_ni+0x1f965
6372de66 mscorlib_ni+0x33de66
5b72f934 System_Runtime_WindowsRuntime_ni+0x1f934
5b6bff16 Windows_UI_ni+0x9ff16
64492a36 clr!COMToCLRDispatchHelper+0x28
0:006> !sos.pe
The call to LoadLibrary(sos) failed, Win32 error 0n2
"The system cannot find the file specified."
Please check your debugger configuration and/or network access.
0:006> .loadby sos clr
The call to LoadLibrary(c:\symbols\clr.dll\52E0B78469b000\sos) failed, Win32 error 0n126
"The system cannot find the file specified."
Please check your debugger configuration and/or network access.
I does not have experience with this kind of debugging and without the instruction I would not have known any of the commands that I had to use in WinDbg.
Does anyone have an idea how to go on from here?
I have uploaded the CrashDump to my OneDrive. Would be great if anyone with more experience could have a look at it:
http://1drv.ms/1gZzrRK
Is it somehow possible to get additional information from the users who reported the crash to the support? Can they extract a crash dump / error report from their systems?
Is there any possibility to supply a changed version to these users to check if these changes influence the problem?
Thank you very much!
In order to get more insight into what your app is doing when it's running on users' devices, you could add logging of some kind. Local logging to file is an option, but a poor one, since you have to let your user dig into hidden files to retreive your application log. It might be acceptable though, depending on your scenario. In that case you might want to look at this logging sample for Windows Store Apps that uses EWT to log.
Alternatives would be using some kind of logging framework. I haven't got any experience in any of those so I couldn't tell you which one to use.
As for getting a changed version to your user: simply build an app-package locally, put it on OneDrive and send them a link to it. They can sideload the app themselves (although it requires running a Powershell script and logging in with a live-account). I've used this approach with several clients and it's workable.

Jess multislot questions

This is for a homework assignment, but I am having a really hard time finding good jess information on the web. I'm trying to use a multislot to to solve a problem, but I can't find anything on how to match the different values. I have this:
(deftemplate patient (slot name)(multislot symptoms))
(deffacts init
(patient (name john) (symptoms very-high-fever cough)))
How can I match the left hand side for just a very-high-fever? This works if I know that the very-high-fever is the first symptom, but I can't be sure of that, so I need to be able to match if a very-high-fever is either symptom.
(defrule high-fever
(patient (name ?n)(symptoms very-high-fever ?))
=>
(printout t ?n " has a high fever." crlf))
I've tried various combinations of field constraints, but I can't seem to get it right and nothing online is giving me any clues.
Thanks.
Use a blank multifield before and after the item you want to match; they match zero or more items. So, something like
(patient (name ?n) (symptoms $? very-high-fever $?))
Will match any patient with the very-high-fever symptom in any position.

Embedded ECL Lisp error handling fetch default error string and possibly line number

Please see #7755661 first. I am using ECL and basically want to execute some code, trap any kind of condition that may occur and then continue execution, without prompting or entering the debugger. This is easy to achieve with the following handler-case macro:
(handler-case
(load "code.lisp") ; this may raise a condition
(error (condition)
(print condition))) ; this prints sth like #<a UNBOUND-VARIABLE>
My only problem is that I cannot find a generic way to print a more meaningful error for the user. Indeed my application is an HTTP server and the output goes to a web page. code.lisp is written by the user and it can raise any kind of condition, I do now want to list them all in my code. I would just like to print the same error message I see on the REPL when I do not use handler-case, but in the HTML page, e.g. for an "unbound variable" error, a string like "The variable VAR is unbound".
By inspecting a condition object of type UNBOUND-VARIABLE I see it has two slots: SI:REPORT-FUNCTION, which is a compiled function and SI:NAME, set to the name of the variable in this case. I guess SI:REPORT-FUNCTION could be what I need to invoke but how can I call it? If I try:
(handler-case foo (error (condition) (SI::REPORT-FUNCTION condition)))
it tells me that SI:REPORT-FUNCTION is undefined. SI or SYS in ECL is a package for functions and variables internal to the implementation, but I don't worry if my code is not portable, as long as it works.
BTW in other kinds of condition objects there are also other apparently useful slots for my purpose, named SI:FORMAT-CONTROL and SI:FORMAT-ARGUMENT, but I cannot access any of them from my code too.
I was looking for somethink alike to the getMessage() method of Java exception objects in Lisp, but none of my sources ever mentions something like that.
Moreover, is there any hope to be able to get the line number in code.lisp where the error occurred too? Without that it would be difficult for the user to locate the problem in his code.lisp source file. I would really want to provide this information and stopping at the first error is acceptable for me.
In Common Lisp when print escaping is disabled, the error message is printed.
CL-USER > (handler-case
a
(error (condition)
(write condition :escape nil)))
The variable A is unbound.
#<UNBOUND-VARIABLE 4020059743>
Note that PRINT binds *print-escape* to T.
Using PRINC works - it binds *print-escape* to NIL.
CL-USER > (handler-case
a
(error (condition)
(princ condition)))
The variable A is unbound.
#<UNBOUND-VARIABLE 4020175C0B>
This is described in CLHS 9.1.3 Printing Conditions.
Also note, when you have an object, which has a slot and the value of this slot is a function, then you need to get the slot value using the function SLOT-VALUE and then use FUNCALL or APPLY and call the function with the correct arguments.
If you have a condition of type simple-condition then it has a format-control and a format-argument information. This is described with an example how to use it for FORMAT in CLHS Function SIMPLE-CONDITION-FORMAT-CONTROL, SIMPLE-CONDITION-FORMAT-ARGUMENTS
My answer below is based on one I already gave at the ECL mailing list. Actually I would claim that this is not an embedding problem, but a Lisp one. You want to get some information at the file position of the form which caused the error. This is not attached to a condition because conditions happen independently of whether the form evaluated was interpreted, compiled or part of a function that is already installed in the Lisp image. In other words, it is up to you to know the position of the file which is being read and do some wrapping that adds the information.
The following is nonstandard and prone to change: ECL helps you by defining a variable ext::source-location when LOAD is used on a source file. This variable contains a CONS that should NEVER be changed or stored by the user, but you can get the file as (CAR EXT:*SOURCE-LOCATION*) and the file position as (CDR EXT:*SOURCE-LOCATION*). The plan is then to embed your LOAD form inside a HANDLER-BIND
(defparameter *error-message* nil)
(defparameter *error-tag* (cons))
(defun capture-error (condition)
(setf *error*
(format nil "At character ~S in file ~S an error was found:~%~A"
(cdr ext:*source-location*)
(car ext:*source-location*)
condition)))
(throw *error-tag* *error-message*))
(defun safely-load (file)
(handler-bind ((serious-condition #'capture-error))
(catch *error-tag*
(load file)
nil)))
(SAFELY-LOAD "myfile.lisp") will return either NIL or the formatted error.
In any case I strongly believe that relying on LOAD for this is doomed to fail. You should create your own version of LOAD, starting from this
(defun my-load (userfile)
(with-open-file (stream userfile :direction :input :external-format ....whateverformat...)
(loop for form = (read stream nil nil nil)
while form
do (eval-form-with-error-catching form))))
where EVAL-FORM-.... implements something like the code above. This function can be made more sophisticated and you may keep track of file positions, line numbers, etc. Your code will also be more portable this way.
So please, read the ANSI Spec and learn the language. The fact that you did not know how to print readably a condition and instead tried to play with ECL internals shows that you might face further problems in the future, trying to go with non-portable solutions (hidden slot names, report functions, etc) instead of first trying the standard way.

An exported aliases symbol doesn't exist in PDB file (RegisterClipboardFormat has RegisterWindowMessage internal name)

I'm trying to set a breakpoint in user32!RegisterClipboardFormat
Evidently, this function is exported (link /dump /exports - it is right there). Before downloading the PDB file from the Microsoft symbol server, I'm able to find this function:
0:001> lm m user32
start end
76eb0000 76fcf000 USER32 (export symbols) c:\Windows\system32\USER32.dll
0:001> x user32!RegisterClipboardFormat*
76ec4eae USER32!RegisterClipboardFormatA (<no parameter info>)
76ec6ffa USER32!RegisterClipboardFormatW (<no parameter info>)
No problems. I'm able to 'bu' any of these functions. But when I download the PDB symbols from the Microsoft PDB server:
0:001>
start end module name
76d50000 76e6f000 USER32 (pdb symbols) c:\symbols\user32.pdb\561A146545614951BDB6282F2E3522F72\user32.pdb
0:000> x user32!RegisterClipboardFormat
WinDBG cannot find the symbols. However, it can find RegisterWindowMesssage:
0:000> x user32!RegisterWindowMessage*
76d64eae USER32!RegisterWindowMessageA = <no type information>
76d66ffa USER32!RegisterWindowMessageW = <no type information>
Note that the functions have the same addresses (This is on Windows 8. Not sure about previous versions). This is probably achieved by the optimizer or in the DEF file (func1=func2 in the EXPORT section). 'link /dump /exports' shows RegisterWindowMessage and RegisterClipboardFormat have the same RVA.
Problem is that I spent way too much time on this. So my questions are:
Is there is an easy way, from within WinDBG to find out missing aliased export symbols.
Say I want to break only on RegisterClipboardFormatW. If I recall correctly, there should be a JMP instruction somewhere (in the calling module import table). How do I find that symbol? Is there a way to find this entry in all calling modules?
Since RegisterWindowMessage and RegisterClipboardFormat have the same RVA, they share the same implementation. Apparently Windows does not make any distinction between the two and both clipboard format and window messages share the same domain of identifiers.
For your first question -- how to find out which implementation function corresponds to exported function. (assuming you have symbols fixed up) First figure out RVA of the export:
C:\>link /dump /exports C:\Windows\Syswow64\user32.dll |findstr RegisterClipboardFormat
2104 24F 00020AFA RegisterClipboardFormatA
2105 250 00019EBD RegisterClipboardFormatW
Then in WinDbg find starting address where DLL is loaded from. Commands lm or lml list all modules, you just need to find the module you are after:
0:001> lml
start end module name
75460000 75560000 USER32
Using RVA as offset to the starting address, get symbol that corresponds to it:
0:002> ln 75460000+00020AFA
(75480afa) USER32!RegisterWindowMessageA | (75480b4a) USER32!MsgWaitForMultipleObjects
Exact matches:
0:002> ln 75460000+00019EBD
(75479ebd) USER32!RegisterWindowMessageW | (75479eea) USER32!NtUserGetProcessWindowStation
Exact matches:
So here we actually found out that RegisterClipboardFormat actually calls into RegisterWindowMessage.
Your second question -- how to put breakpoint only on RegisterClipboardFormat, and not on RegisterWindowMessage. In general it is impossible, because they share the same implementation. For example, your app might call GetProcAddress("RegisterClipboardFormat") and you will have hard time figuring out if it called to one function or another. However if you know that the call was made through imported function, then you can do this. All imported functions are declared in import address table in your application. If you put an access breakpoint on the entry in import address table, you can break before the call is made. This might be compiler specific, but I know that Visual C++ assigns symbolic names to entries in import address table. In this case putting breakpoint is easy:
ba r4 MyModule!_imp_RegisterClipboardFormatA