ioctl_nsfs

#include <linux/nsfs.h>  /* Definition of NS_* constants */
#include <sys/ioctl.h>

int ioctl(int fd, unsigned long op, ...);

ENOTTY

fd does not refer to a /proc/pid/ns/* file.

Linux.

ioctl(2), fstat(2), proc(5), namespaces(7)