C: do {...} while(0)?

Posted by igul222 on Stack Overflow See other posts from Stack Overflow or by igul222
Published on 2010-04-22T00:58:13Z Indexed on 2010/04/22 1:03 UTC
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I'm working on some C code filled with macros like this:

#define SAFE_FREE(x) do { if ((x) != NULL) {free(x); x=NULL;} } while(0)

Can anyone explain what this macro does, and why do {} while(0) is needed? Wouldn't that just execute the code once?

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C: do {...} while(0)?

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