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--- programming:bash:overflow [2022/03/30 15:30] – Creating overflow ateixeira
+++ programming:bash:overflow [2022/03/31 15:07] (current) – [Interesting fact :] ateixeira
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+====== Overflow ======
+It will depend on your version of bash, your OS((Operating System)) and your CPU((Processor)) architecture. To try it, we will set a variable to (2^16). If the output is the right answer, we will set it to (2^32), and so on untill the answer is not right anymore.
+In the example below, we can see that at (2^64) the answer is not right anymore. So we substract 1 at the result  (2^64) - 1  to know if it is a non-signed INT and we see that the answer is not right yet. So we substract 1 to the exponent (2^63) to know if it is a signed INT and ... the answer still wrong.
+Then we substract 1 at the result  (2^63) - 1 and we see that the result is the answer we were waiting for. We can therefore deduce that it is a signed 64 bit INT. To prove it, we add 1 to the variable and we can see the MIN limit signed INT.
+We have now the MIN and the MAX limit.
+==== Example ====
   #!/bin/bash
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-Output will be:
+==== Output will be : ====
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   9223372036854775908           #String
   -9223372036854775707          #INT overflow
+==== Interesting fact : ====
+> At the end, we set a variable bigger than the MAX limit and increment X (in this case X=1). The variable is at first stocked as a STR but when we force it to increment by X, we see that bash will compensate and output the MIN limit incremented by X.