getting fileinput to do errors='ignore' or 'replace'?

[Terry Reedy]

On 12/3/2015 10:18 AM, Adam Funk wrote:
> On 2015-12-03, Adam Funk wrote:
>
>> I'm having trouble with some input files that are almost all proper
>> UTF-8 but with a couple of troublesome characters mixed in, which I'd
>> like to ignore instead of throwing ValueError.  I've found the
>> openhook for the encoding
>>
>> for line in fileinput.input(options.files, openhook=fileinput.hook_encoded("utf-8")):
>>      do_stuff(line)
>>
>> which the documentation describes as "a hook which opens each file
>> with codecs.open(), using the given encoding to read the file", but
>> I'd like codecs.open() to also have the errors='ignore' or
>> errors='replace' effect.  Is it possible to do this?
>
> I forgot to mention: this is for Python 2.7.3 & 2.7.10 (on different
> machines).

fileinput is an ancient module that predates iterators (and generators) 
and context managers. Since by 2.7 open files are both context managers 
and line iterators, you can easily write your own multi-file line 
iteration that does exactly what you want.  At minimum:

for file in files:
     with codecs.open(file, errors='ignore') as f
     # did not look up signature,
         for line in f:
             do_stuff(line)

To make this reusable, wrap in 'def filelines(files):' and replace 
'do_stuff(line)' with 'yield line'.

-- 
Terry Jan Reedy