c - What does the : do in a struct declaration after a member

Question

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

In:

struct foo {
  unsigned bar : 2;
};

What does the ': 2' do?

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1 Answer

深蓝 · Answer 1 · 2021-10-23T21:31:54+0000

answered Oct 24, 2021 by 深蓝 (71.8m points)

It declares a bit field. The number specifies the size of that member in bits.

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