Of course, both are junk. Why would you only read the first 20,000 bytes?

There are a lot of scenarios where you might want to read the first part of a file without reading the whole file. I think there are some Unix file commands that read the first 1-2K of a file to determine if the file is text or binary? Perhaps I want to concatenate some big .WAV files together. There is some header info at the beginning of these files that needs to be interpreted. In the OP's question, this is a single .jpg and there is no reason to read the file in "hunks" because the image has to be processed as a single unit. However, other scenarios do exist.

I do commend you for the choice of 8*1024 as buf size. That is a very good number with most file systems. Certain byte boundaries are important for the file system to work efficiently.

In reply to Re^7: Error binmode() on unopened filehandle by Marshall
in thread Error binmode() on unopened filehandle by RedJeep

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