Could someone please give me an example of when and why we would use bitwise operators. I'm trying to build a detailed understanding as to what and why we use such things.
One example I know of is the << left shift being used for the power of.
What else would it be used for?
Looking at the & I can predict and produce the expected results as per the tutorial but why would we need to do such an operation.
Many thanks
Here's an example, from a very recent post: How to split an int, into 2-Bytes???? Controlling PWM with an int.
There's also this thread.
Most file formats formats will describe how integer values are stored in the bytes 0,1,2,3
Which maybe different from actual byte order of the integer value on the current platform.
So to write portable code you
1. Read int as whole and then call something like ntos which will swap bytes if platform requires it.
2. Or read bytes as array and then assemble integer from it using bit shifting and ORing
The stream formats go further - describing fields as bit position Like CMR field takes 4 low bits of first byte of AMR payload of each RTP packet...
In this case to extract the field value you HAVE to use the bit shifting and masking
Same goes for opposite direction operations - when you want to store the file of specific format in portable way or generate outgoing stream according to its format requirements
All problems in computer science can be solved by another level of indirection,
except for the problem of too many layers of indirection.
– David J. Wheeler
Well, there's all these sorts of things:
Bit Twiddling Hacks
My homepage
Advice: Take only as directed - If symptoms persist, please see your debugger
Linus Torvalds: "But it clearly is the only right way. The fact that everybody else does it some other way only means that they are wrong"
