bug#56443: 28.1; Mac segmentation fault with ffap

[Stephen Eglen]

Thanks everyone for help debugging this.
 
> BTW, I don't really understand the semantics of
> file-name-case-insensitive-p.  The docstring says that it returns nil if
> the file is not found, but these calls return t on my system:
>
> (file-name-case-insensitive-p "")
> (file-name-case-insensitive-p "FileThatDoesNotExist")

I also find that those two expressions return t on my mac, and nil on my
linux machine.  This seems to be consistent with the doc string:


  Return t if file FILENAME is on a case-insensitive filesystem.  Return
  nil if FILENAME does not exist or is not on a case-insensitive
  filesystem, or if there was trouble determining whether the filesystem
  is case-insensitive.

It returns t on mac as it is case-insensitive by default, presumbly
irrespective of whether the file exists.

One small suggestion for the docstring might be to remove the double
negative in the second sentence:

"is not on a case-insensitive filesystem"

could be

"is on a case-sensitive filesystem"

?

Stephen