uintptr(unsafe.Pointer(buf)),
		size,
		uintptr(unsafe.Pointer(result)),
		0)
	return syscall.Errno(errno)
}

//go:cgo_import_dynamic libc_getpwuid_r getpwuid_r  "/usr/lib/libSystem.B.dylib"
func libc_getpwuid_r_trampoline()

func Getpwuid(uid uint32, pwd *Passwd, buf *byte, size uintptr, result **Passwd) syscall.Errno {
	// Note: Returns an errno as its actual result, not in global errno.

resolving user and group ids to names, and listing supplementary group IDs.
One is written in pure Go and parses /etc/passwd and /etc/group. The other
is cgo-based and relies on the standard C library (libc) routines such as
getpwuid_r, getgrnam_r, and getgrouplist.

When cgo is available, and the required routines are implemented in libc
for a particular platform, cgo-based (libc-backed) code is used.

#include <sys/types.h>
#include <pwd.h>
#include <grp.h>
#include <stdlib.h>
#include <string.h>

static struct passwd mygetpwuid_r(int uid, char *buf, size_t buflen, int *found, int *perr) {
	struct passwd pwd;
	struct passwd *result;
	memset (&pwd, 0, sizeof(pwd));
	*perr = getpwuid_r(uid, &pwd, buf, buflen, &result);
	*found = result != NULL;
	return pwd;
}

	buf := make([]byte, kind.initialSize())
	for {
		errno := f(buf)
		if errno == 0 {
			return nil
		} else if runtime.GOOS == "aix" && errno+1 == 0 {
			// On AIX getpwuid_r appears to return -1,
			// not ERANGE, on buffer overflow.
		} else if errno != syscall.ERANGE {
			return errno
		}
		newSize := len(buf) * 2
		if !isSizeReasonable(int64(newSize)) {

	return pwd, result != nil, errno
}

func _C_getpwuid_r(uid _C_uid_t, buf *_C_char, size _C_size_t) (pwd _C_struct_passwd, found bool, errno syscall.Errno) {
	var result *_C_struct_passwd
	errno = unix.Getpwuid(uid, &pwd, buf, size, &result)
	return pwd, result != nil, errno
}

func _C_getgrnam_r(name *_C_char, buf *_C_char, size _C_size_t) (grp _C_struct_group, found bool, errno syscall.Errno) {
	var result *_C_struct_group