ns_get_owner_uid(2const) - BetterMan

ns_get_owner_uid(2const)

discovering the owner of a user namespace

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Synopsis

#include <linux/nsfs.h>
  /* Definition of 
NS_GET_OWNER_UID
 */
#include <sys/ioctl.h>
int ioctl(int 
fd
, NS_GET_OWNER_UID, uid_t *
uid
);

—

Options · 1

EINVAL

fd does not refer to a user namespace.

NAME

NS_GET_OWNER_UID - discovering the owner of a user namespace

SYNOPSIS

bash

#include <linux/nsfs.h>\n  /* Definition of \nNS_GET_OWNER_UID\n */
\n#include <sys/ioctl.h>

bash

int ioctl(int \nfd\n, NS_GET_OWNER_UID, uid_t *\nuid\n);

DESCRIPTION

The NS_GET_OWNER_UID operation can be used to discover the owner user ID of a user namespace (i.e., the effective user ID of the process that created the user namespace).

fd refers to a /proc/pid/ns/user file.

The owner user ID is returned in the uid_t pointed to by the third argument.

RETURN VALUE

On success, 0 is returned. On error, -1 is returned, and errno is set to indicate the error.

ERRORS

EINVAL: fd does not refer to a user namespace.

STANDARDS

Linux.

HISTORY

Linux 4.11.