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How this works?

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# 8  
Old 08-31-2010
Quote:
Originally Posted by pludi
fork in this case is not a variable.
Indeed, it is a constant.
Quote:
Also, if you'd have compiled with warnings enabled, or read them, you'd have seen something like this:
Code:
warning: the address of ‘fork' will never be NULL

What compiler gives you that warning ?
Neither gcc with most warnings enabled (-Wall), nor Sun cc seem to choke on that code.
# 9  
Old 08-31-2010
But while checking the sizeof() to fork its showing 1.Smilie
# 10  
Old 08-31-2010
Depends on the compiler. Gcc indeed (wrongly) thinks fork size is 1 but cc is complaining:
Code:
"a.c", line 5: cannot take sizeof function: fork

This User Gave Thanks to jlliagre For This Post:
carolsanjeevi
# 11  
Old 08-31-2010
Quote:
Originally Posted by jlliagre
Indeed, it is a constant.What compiler gives you that warning ?
Neither gcc with most warnings enabled (-Wall), nor Sun cc seem to choke on that code.
Compiled with gcc. And it didn't choke on it, it was just a warning (-Wall)
This User Gave Thanks to pludi For This Post:
carolsanjeevi
# 12  
Old 08-31-2010
Broadly speaking, it "works" because variables and functions are both just memory locations; the difference is what's stored there and how it's used.
This User Gave Thanks to Corona688 For This Post:
carolsanjeevi
# 13  
Old 08-31-2010
Quote:
Originally Posted by pludi
Compiled with gcc. And it didn't choke on it, it was just a warning (-Wall)
Got it. This warning appears with ggc4 but not gcc3 which I was testing. The sizeof bug is still there with gcc4 though.
This User Gave Thanks to jlliagre For This Post:
carolsanjeevi
# 14  
Old 09-01-2010
Seems this is a deliberate extension on the standard: Using and Porting the GNU Compiler Collection (GCC): C Extensions. With -pedantic it will complain about it.
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