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following is a simple embedded c piece of code, can somebody tell me is there a problem in it ?
i am new to embedded programming. It will be great help, any pointers to this ...
thanks
pdk
c Syntax (Toggle Plain Text)
thanks
pdk
Last edited by Narue : Jul 12th, 2008 at 9:44 am. Reason: Added code tags
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>can somebody tell me is there a problem in it ?
Assuming boolean is a typedef, there's nothing syntactically or semantically wrong with that function. Perhaps if you told us what it's supposed to do, we can tell you if it actually does it.
Assuming boolean is a typedef, there's nothing syntactically or semantically wrong with that function. Perhaps if you told us what it's supposed to do, we can tell you if it actually does it.
I'm here to prove you wrong.
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it was asked for me in the test. where they asked me
1.what the code does and
2. the potential problem with that.
i answered, If any of the last 3 lsb bits of the number is set to '1' return '0'. Else return 1. and i could not see any potential problem in that..
1.what the code does and
2. the potential problem with that.
i answered, If any of the last 3 lsb bits of the number is set to '1' return '0'. Else return 1. and i could not see any potential problem in that..
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Your analysis is correct.
But whether there is anything 'wrong' depends on what it's supposed to do.
If for example is was a test to see if a number was >= 8, then it would fail miserably on negative numbers.
The name 'new' certainly doesn't help.
But whether there is anything 'wrong' depends on what it's supposed to do.
If for example is was a test to see if a number was >= 8, then it would fail miserably on negative numbers.
The name 'new' certainly doesn't help.
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
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thankyou for the reply.
but i am not sure whether this logic will work ( i.e to check whether the number is >=8) .. as lets say for eg +9 , the program still returns '0'
but i am not sure whether this logic will work ( i.e to check whether the number is >=8) .. as lets say for eg +9 , the program still returns '0'
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True.
So what's the indented function then?
If we don't know what it's supposed to do, how can we say whether it's right or wrong?
So what's the indented function then?
If we don't know what it's supposed to do, how can we say whether it's right or wrong?
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
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even i was not sure. because in the test, i was supposed to tell what the function is intended to do and any potential problems !!!.
i could not exactly figure out this .. i.e why any pointers to this will be helpful.
as pointed out, i was also thinking whether it will cause any problems for -ve numbers .. but without any potential soln..
i could not exactly figure out this .. i.e why any pointers to this will be helpful.
as pointed out, i was also thinking whether it will cause any problems for -ve numbers .. but without any potential soln..
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This function resave number, if the number is 0 its return true else its return false.
The Boolean " a & 7 ;" says if a != 0 and 7 != 0 then 1 else 0
Has you see the 7 is not needed
The Boolean " a & 7 ;" says if a != 0 and 7 != 0 then 1 else 0
Has you see the 7 is not needed
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Posting Whiz in Training
The only potential problem you can be sure about is that 'boolean' isn't a standard type.
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This function resave number, if the number is 0 its return true else its return false.
The Boolean " a & 7 ;" says if a != 0 and 7 != 0 then 1 else 0
Has you see the 7 is not needed
--------------------------------
when the number is lets say '8'. it still returns '1' .. i.e basically numbers for which lsb 3 bits are not set. it will return '1'
The Boolean " a & 7 ;" says if a != 0 and 7 != 0 then 1 else 0
Has you see the 7 is not needed
--------------------------------
when the number is lets say '8'. it still returns '1' .. i.e basically numbers for which lsb 3 bits are not set. it will return '1'
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