Why does struct have two variable names in C/C++

Question

In the below code why does the struct have two variable names?

#include <sys/resource.h>

int main (int argc, char **argv)
{
    const rlim_t kStackSize = 64L * 1024L * 1024L;

    struct rlimit rl;    //HERE

    int result = getrlimit(RLIMIT_STACK, &rl);


    return 0;
}

It has one variable name: `rl`. If this is C++, the `struct` isn't needed, and if this is C, you can change the type so it isn't needed. — chris, Apr 01 '14 at 00:45

score 2 · Accepted Answer · answered Apr 01 '14 at 00:46

2

In C, struct with its tag together is a name, unless it's typedefed.

In C++, you can omit the struct keyword.

answered Apr 01 '14 at 00:46

Yu Hao

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Ah so rlimit is a "type" of struct? – user997112 Apr 01 '14 at 00:49
@user997112 In C, `struct rlimit` is a type, `rlimit` alone is just a struct tag. – Yu Hao Apr 01 '14 at 00:50

score 1 · Answer 2 · edited May 23 '17 at 11:49

1

If this is C, the struct is just to tell C that it is in a different namespace.

See: understanding C namespaces

If this is C+++, then the struct is not needed.

edited May 23 '17 at 11:49

Community

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answered Apr 01 '14 at 00:47

Leif Andersen

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Why does struct have two variable names in C/C++

2 Answers2