How to detect safe mode on OSX

Question

I have some code that I only want to run if the user didn't boot in safe mode. Is there a way using the CoreFoundation or C standard APIs that I can detect that?

EDIT: here is my code thanks to my accepted answer:

#include <sys/sysctl.h>
...

int safeBoot;
int mib_name[2] = { CTL_KERN, KERN_SAFEBOOT };
size_t length = sizeof(safeBoot);

if (!sysctl(mib_name, 2, &safeBoot, &length, NULL, 0)) {
    if (safeBoot == 1) {
        // We are in safe mode
    } else {
        // Normal mode. Continue…
    }
} else {
    // Couldn't find safe boot information
}

Answer 1

You can use sysctl like this:

sysctl -n kern.safeboot

It gives 1 when in safe boot mode and 0 when in normal mode.