How to compile the size of a graphic file for a pure ASP program

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'::: :::
'::: This routine'll attempt to identify any filespec passed:::
'::: As a graphic file (regardless of the extension). This would:::
'::: Work with BMP, GIF, JPG and PNG files. :::
'::: :::
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'::: Based on ideas presented by David Crowell:::
'::: (Credit where due)::
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'::: blah blah blah blah blah blah blah blah-blah blah blah blah:::
'::: blah blah blah blah blah blah blah blah-blah blah blah blah:::
'::: blah blah Copyright *c* MM, Mike Shaffer blah blah:::
'::: blah blah all RIGHTS RESERVED worldwide blah:::
'::: Blah blah Permission is granted to use this code blah:::
'::: Blah blah in your projects, as long as this blah blah:::
'::: blah blah copyright notice is included blah blah:::
'::: blah blah blah blah blah blah blah blah-blah blah blah blah:::
'::: blah blah blah blah blah blah blah blah-blah blah blah blah:::
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'::: :::
':: This function gets a specified number of bytes from::
'::: File, starting at the offset (base 1):::
'::: :::
'::: Passed::::
'::: flnm => filespec of file to read:::
'::: Offset => offset at which to start reading:::
'::: bytes => How many bytes to read::
'::: :::
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function GetBytes (flnm, offset, bytes)
Dim objFSO
Dim objftemp
Dim objTextStream
Dim lngsize