Curious issue with simple code

[Fredrik Lundh]

codefire wrote:

> As above it all works as expected. However, on the marked line, if I
> use f instead of fp then that condition returns false! Surely,
> isfile(f) should return true, even if I just give a filename, rather
> than the full path? 

try printing both "f" and "fp", and see if you can tell the difference 
between the two filenames...

</F>