but引导的是定语从句吗

but引导的是定语从句吗?

请问这是由关系代词but引导的定语从句？

There is no man but feels pity for starving children. 如何理解？

But 也可以用作关系代词引导定语从句，用于否定词汇之后，在语义上等于that/who…not。

There are very few but admire his talents.

极少有人不钦佩他的才能。

There is no man but feels pity for starving children.

无人对挨饿的孩子们不同情。

There is no difficulty but be overcome. 没克服不了的困难。

There is nobody but knows of him.

无人不认识他。