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.TH KEYCTL_CHOWN 2const 2024-08-21 "Linux man-pages 6.10"
.SH NAME
KEYCTL_CHOWN
\-
change the ownership of a key
.SH LIBRARY
Standard C library
.RI ( libc ,\~ \-lc )
.SH SYNOPSIS
.nf
.BR "#include <linux/keyctl.h>" "  /* Definition of " KEY* " constants */"
.BR "#include <sys/syscall.h>" "   /* Definition of " SYS_* " constants */"
.B #include <unistd.h>
.P
.BI "long syscall(SYS_keyctl, KEYCTL_CHOWN, key_serial_t " key ,
.BI "             uid_t " uid ", gid_t " gid );
.fi
.SH DESCRIPTION
Change the ownership (user and group ID) of a key.
.P
.I key
contains the key ID.
.I uid
contains the new user ID (or \-1 in case the user ID shouldn't be changed).
.I gid
contains the new group ID (or \-1 in case the group ID shouldn't be changed).
.P
The key must grant the caller
.I setattr
permission.
.P
For the UID to be changed, or for the GID to be changed to a group
the caller is not a member of, the caller must have the
.B CAP_SYS_ADMIN
capability (see
.BR capabilities (7)).
.P
If the UID is to be changed, the new user must have sufficient
quota to accept the key.
The quota deduction will be removed from the old user
to the new user should the UID be changed.
.SH RETURN VALUE
On success,
0 is returned.
.P
On error, \-1 is returned, and
.I errno
is set to indicate the error.
.SH VERSIONS
A wrapper is provided in the
.I libkeyutils
library:
.BR keyctl_chown (3).
.SH STANDARDS
Linux.
.SH HISTORY
Linux 2.6.10.
.SH SEE ALSO
.BR keyctl (2),
.BR keyctl_chown (3)