如何在OS X中使用objective c獲取父進程ID？

Question

我有一些進程的PID，需要獲取父進程ID。如何使用目標c獲取它？

Answer 1

原始來源：http://www.objectpark.net/parentpid.html

#include <sys/sysctl.h> 

#define OPProcessValueUnknown UINT_MAX 

int ProcessIDForParentOfProcessID(int pid) 
{ 
    struct kinfo_proc info; 
    size_t length = sizeof(struct kinfo_proc); 
    int mib[4] = { CTL_KERN, KERN_PROC, KERN_PROC_PID, pid }; 
    if (sysctl(mib, 4, &info, &length, NULL, 0) < 0) 
     return OPProcessValueUnknown; 
    if (length == 0) 
     return OPProcessValueUnknown; 
    return info.kp_eproc.e_ppid; 
}