Exceptions in micro python

[kjm]

try:
    1/0
except Exception as e:
    sys.print_exception(e)

produces

division by zero
Traceback (most recent call last):
  File "<stdin>", line 4, in <module>
ZeroDivisionError: division by zero

But I'd like to be able to store the error and the line number that produced it in a file instead of printing it. Storing the error is easy enough

with open('ErrorFile', 'wb') as f: f.write(str(e))

but I can't figure out a way to access & store the line number. Anyone out there in the pycom firmament mastered this trick?

[Eric73]

@kjm in documentation function prototype is

sys.print_exception(exc, file=sys.stdout)

Have you try to open a file and use it with sys.print_exception to see what happened inside the file?
(Sorry i have no module to test)

[robert-hh]

@eric73 just tried thst on windows MP. If you open a file beforehand, you can use that file handle as second argument to sys.print_exception.

[kjm]

not on the gpy you can't!

[robert-hh]

@kjm I'll have to check that tonight. I have no device here at the moment.

[kjm]

Anybody out there manage to store traceback line numbers to a file on the gpy?

[robert-hh]

@kjm You could do as follows:

try:
    1/0
except Exception as e:
    import sys
    with open("error.log", "a") as f:
        sys.print_exception(e, f)

This works for me,
Pycom MicroPython 1.20.0.rc6 [8d824a0-dirty] on 2019-01-28; FiPy with ESP32

[kjm]

Ah, perfect! Tanks muchly.

[kjm]

Hey Robert I need to filter out the double inverted commas before I store in the error.log file I tried

err=sys.print_exception(e)
err=err.replace('"',"")

but I got AttributeError: 'NoneType' object has no attribute 'replace'

[robert-hh]

@kjm follow these steps. I just executed at the prompt:

>>> from uio import StringIO
>>> import sys
>>> s = StringIO()
>>> try:
...     1/0
... except Exception as e:
...     sys.print_exception(e, s)
...
>>> x=s.getvalue()
>>> x
'Traceback (most recent call last):\n  File "<stdin>", line 2, in <module>\nZeroDivisionError: divis
ion by zero\n'
>>>

[kjm]

Thnx again Robert, for anyone else with a similar requirement I ended up with....

except Exception as e:
  import sys; from uio import StringIO
  s=StringIO(); sys.print_exception(e, s)  
  s=s.getvalue(); s=s.split('\n')                                                                   
  line=s[1].split(','); line=line[1]; error=s[2]; err=error+line; print(err)
  with open ('error.log', 'a') as f: f.write(err) 

[ronald gevern]

This post is deleted!