[boost] Re: [Filesystem] i18n

From: Martin (adrianm_at_[hidden])
Date: 2005-04-05 01:47:41

> To me, an io error does imply some kind of failure, and a serious one at 
> that. Remember that errors reported by the system API call (stat() or 
> similar) have been analyzed, and those that clearly indicate existance or 
> not are not treated as errors. What is left are error codes that represent 
> either hard errors, or conditions which are ambiguous as to the true status.

I agree partly but there are 2 cases here.

1. The is_x are used as filter.
Since there is no filtering directory_iterator available you need to use the 
is_x function to the filtering. In many cases you just want to iterate over 
existing accesible files and/or directories, follow or ignore links. In these 
cases a throw is an inconvenience since it complicates the code without any 
gain.

2. The is_x functions are used to verify user input/configuration or program 
logic follows different paths depending on result of is_x functions.
In this context I fully agree that io errors should throw an exception.

One solution is to keep the current throwing is_x function and add filtering 
capabilities to director_iterator (e.g. itr->is_directory() or itr = 
directory_iterator(path, files_only)). At least on Win32 this should be easy 
since the status is directly availble from the findfirst/findnext functions.