[Octave-bug-tracker] [bug #46493] Incorrect result from fscanf and scanf with %i format

[Rik]

Update of bug #46493 (project octave):

                  Status:                    None => Confirmed              
        Operating System:       Microsoft Windows => Any                    
                 Summary: Incorrect result from fscanf and scanf => Incorrect
result from fscanf and scanf with %i format

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Follow-up Comment #3:

Confirmed using Doug's simplified example from comment #2.

As a simple workaround, if you know that the numbers are in decimal format
then you can use either %u for unsigned or %d for optionally signed integers. 
The following format works


frm = '"%d" ,"%i","%i","%i","%i","%i"\n';
sscanf ('"08"', frm)
ans =  8


The trouble seems to be that %i must recognize decimal, octal, and
hexadecimal.  In this case, the first character of the number is a '0' which
seems to trigger the octal conversion format.  But there is no valid octal
number for 8 and 9 so it returns '0' for that conversion.

On the other hand, anything you do which breaks the recognition of the number
as octal will cause it to work.  For example,


sscanf ('"+08"', frm)
ans =  8
sscanf ('"-08"', frm)
ans = -8


It would be interesting to know if Matlab gets this right.  If anyone has
access, could they run the following two tests?


sscanf ('"09"', '"%i"')
sscanf ('"079"', '"%i"')




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