nil return on mBed?

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Jim_Thorpe Jim_Thorpe
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| nil return on mBed?

Hi all

I'm new this forum and have just discovered eLua for mBed :-)

I have a question regarding the following code, which I would like to use to assess if a file is present on the mBed built-in flash-drive (/SEMI/):

pathandfile = "/semi/1.txt"

file =, 'r')

if file == nil then

        print("File not found")


        print("File found")


When I execute the code, it always returns "File Found", even if the file '1.txt' is not present. To my understanding, should return a nil when there is an issue opening a file (e.g. it does not exist), however, here it doesn't seem to be the case.

If I remove the filename in the 'pathandfile' string altogether (e.g. pathandfile = "/semi/"), then I get a File not Found, however pathandfile = "/semi/blah.txt" when blah.txt doesn't exist still returns 'File found'

Any ideas what I'm doing wrong here?