declaring a "bit" to use as a flag in flowcode 5

[davet]

Hi all!
I am trying to set up some bits as flags (in "C" ), such as:

In the supplementary code window.

bit myflag;

but boostc does not seem to recognise "bit" i.e. it does not highlight in blue.
it states in the boostc manual for example "bit b; //variable will be placed by linker at arbitrary position"

Any help much appreciated!

Dave

[Benj]

Hi Dave,

You can try the following.

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bool myflag;

If I were you I would use say a byte variable and use this to pack 8 bool values. Otherwise your bool values will each likely consume a whole byte anyway on their own. They certainly do for GCC based compilers which surprised me.

Setting a bit in the byte.

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flags = flags | (1 << bitnum)

Clearing a bit in the byte.

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flags = flags & ~(1 << bitnum)

Testing a bit in the byte, as 0 or 1.

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test = (flags & (1 << bitnum)) >> bitnum

bitnum = 0-7

This will also simulate correctly in v5 as you can do it all with calculation icons instead of C icons.

[davet]

Thanks for the quick reply Benj!
Thanks for that solution, makes sense!
Just being pedantic here, why is "bit" not recognised by the complier?
Cheers

Dave

[Benj]

Hi Dave,

Just being pedantic here, why is "bit" not recognised by the complier?

That's a question for the guys at sourceboost probably just goes back to the days pre-GCC where things in C were a bit less well defined.

[davet]

Thanks Benj!