Re: [PATCH 2/4] Add functions get_relative_cwd() and is_inside_dir()

> Johannes Schindelin <Johannes.Schindelin@gmx.de> writes:
>
>> The function get_relative_cwd() works just as getcwd(), only that it
>> takes an absolute path as additional parameter, returning the prefix
>> of the current working directory relative to the given path.  If the
>> cwd is no subdirectory of the given path, it returns NULL.
>> ...
>> +/*
>> + * get_relative_cwd() gets the prefix of the current working directory
>> + * relative to 'dir'.  If we are not inside 'dir', it returns NULL.
>> + * As a convenience, it also returns NULL if 'dir' is already NULL.
>> + */
>> +char *get_relative_cwd(char *buffer, int size, const char *dir)
>> +{
>> +	char *cwd = buffer;
>> +
>> +	if (!dir || !getcwd(buffer, size))
>> +		return NULL;
>
> When is it not a fatal error if get_relative_cwd() is called
> with a NULL dir parameter, or getcwd() fails?
>
> If there is no valid such cases, I would rather have this
> die(), former with "BUG" and the latter with strerror(errno).