Can functions return NULL value?

Can a function, written in C, return a NULL value?
I would like write code like this:

text * getnull (text * t)
{
return NULL;
}

but it doesn't work, the backend terminates abnormally.

Thanks a lot

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Andrea Austa - aausta(at)athena(dot)polito(dot)it
Debian GNU/Linux User
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