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Date: Fri, 14 Jan 2022 19:30:25 +0100
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From: DrPi <314@drpi.fr>
Subject: Usage of Stream Set_Index() function
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Hi,

I'm writing an application where I read a file with a complex structure.
For this, I use Ada.Streams.Stream_IO package.
To read the file, I need to position the file pointer to the correct 
location. I do this using Set_Index().

In ARM A.12.1, it is stated :
For Read and Write with a Positive_Count parameter, the value of the 
current index is set to the value of the Positive_Count parameter plus 
the number of stream elements read or written.

I don't understand the "plus the number of stream elements read or written".

Does this mean one can't go back to beginning of file once data have 
been read ?

Nicolas