KEYCTL_UPDATE(2const)                                    KEYCTL_UPDATE(2const)

NAME
       KEYCTL_UPDATE - update a key's data payload

LIBRARY
       Standard C library (libc, -lc)

SYNOPSIS
       #include <linux/keyctl.h>  /* Definition of KEY* constants */
       #include <sys/syscall.h>   /* Definition of SYS_* constants */
       #include <unistd.h>

       long syscall(SYS_keyctl, KEYCTL_UPDATE, key_serial_t key,
                    void payload[.size], size_t size);

DESCRIPTION
       Update a key's data payload.

       key specifies the ID of the key to be updated.  payload points to the
       new payload and size contains the new payload size in bytes.

       The caller must have write permission on the key specified and the key
       type must support updating.

       A negatively instantiated key (see KEYCTL_REJECT(2const)) can be
       positively instantiated with this operation.

RETURN VALUE
       On success, 0 is returned.

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

ERRORS
       The key type does not support updating.

VERSIONS
       A wrapper is provided in the libkeyutils library: keyctl_update(3).

STANDARDS
       Linux.

HISTORY
       Linux 2.6.10.

SEE ALSO
       keyctl(2), keyctl_update(3)

Linux man-pages 6.10              2024-08-21             KEYCTL_UPDATE(2const)