Wise monks: I have a function that examines JPEG files to find the image height and width. Four getc's are used to read four consecutive bytes. The function has been running for years with no problem, but on one particular file, getc" skips ahead after reading each character.

By using "tell" I can see where the file pointer is. Normally tell returns something like this: 270, 271, 272, 273. However, in the problem file, it returns 270, 782, 4367, 4368.

The problem occurs on two different servers. I thought the file was corrupted, but it looks normal using a hex editor, and it opens correction in MS Photo Ed, which also can determine the image size (in other words, Photo Ed can read the bytes I can't seem to read).

Why would getc skip like this? I've Googled and searched this site to no avail.

Many thanks in advance for any wisdom!

Stephen

In reply to getc skips ahead by Stephen Toney

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