Re: [Zope] PIL: can't call same method twice

6 Mar 2005


      Hi Dieter,
...
Almost surely, your first call moved the file pointer to
  the end and the second one does not find content.
You can use the "seek" method to reposition the file pointer.
That is, what I thought, too. So I added in PIL.Image.py (Version 1.1.4)
in line 1548 "fp.seek(0)" to "rewind" the file object (see below) to no
avail. So I guess I am not in the right place. But I will dig into the
PIL code soon.
Thanx for pointing me in the right direction.
Regards Chris

# PIL.Image.py
# Opens and identifies the given image file.
def open(fp, mode="r"):
     "Open an image file, without loading the raster data"

     if mode != "r":
         raise ValueError("bad mode")

     if isStringType(fp):
         import __builtin__
         filename = fp
         fp = __builtin__.open(fp, "rb")
     else:
         filename = ""
     fp.seek(0)            # NEW LINE: rewind the object
     prefix = fp.read(16)
     # [...] continue to identify the the image