What's the usage of char buf[0] as a structure element?

[Kok How Teh]

Hi;
I see many "char buf[0];" structure element used in linux kernel
especially in include/net/*.h Could anyone explain what's the use of
this "zero-element" array as an element in a structure? Thanks.

Regards.

 

[Alexander Bartolich]

[...]
I see many "char buf[0];" structure element used in linux kernel
especially in include/net/*.h Could anyone explain what's the use of
this "zero-element" array as an element in a structure? Thanks.

http://c-faq.com/struct/structhack.html

--

 

[Eric Sosman]

Hi;
I see many "char buf[0];" structure element used in linux kernel
especially in include/net/*.h Could anyone explain what's the use of
this "zero-element" array as an element in a structure? Thanks.

This is Question 2.6 in the comp.lang.c Frequently Asked
Questions (FAQ) at <http://www.c-faq.com/>. Your other thread
"dynamic buffer allocation at char buf[1]" is a variation on
the same question.

 

[Seebs]

Hi;
I see many "char buf[0];" structure element used in linux kernel
especially in include/net/*.h Could anyone explain what's the use of
this "zero-element" array as an element in a structure? Thanks.

It's a pre-C99 version of a flexible array member.

-s