c - What is the difference between NUL and NULL? -

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• what difference between null, '\0' , 0 11 answers

null macro defined in <stddef.h> null pointer; can defined ((void*)0). null name of first character in ascii character set. difference between them?

there no such term nul in c standard. in c standard there used following terms

null character (\0) null macro null pointer null pointer constant null preprocessing directive null statement null wide character 

for example

...a byte bits set 0, called null character, shall exist in basic execution character set; used terminate character string.

or

3 integer constant expression value 0, or such expression cast type void *, called null pointer constant.66) if null pointer constant converted pointer type, resulting pointer, called null pointer, guaranteed compare unequal pointer object or function.