NS_GET_OWNER_UID(2const) — Linux manual page

NS_GET_OWNER_UID(2const)                         NS_GET_OWNER_UID(2const)

NAME         top

       NS_GET_OWNER_UID - discovering the owner of a user namespace

SYNOPSIS         top

       #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);

DESCRIPTION         top

       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         top

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

ERRORS         top

       EINVAL fd does not refer to a user namespace.

STANDARDS         top

       Linux.

HISTORY         top

       Linux 4.11.

SEE ALSO         top

       ioctl(2), ioctl_nsfs(2)

COLOPHON         top

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Linux man-pages 6.15            2025-05-17       NS_GET_OWNER_UID(2const)

Pages that refer to this page: ioctl_nsfs(2)

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