NAME

       keyctl_update - update a key

SYNOPSIS

       #include <keyutils.h>

       long keyctl_update(key_serial_t key, const void *payload,
       size_t plen);

DESCRIPTION

       keyctl_update() updates the payload of a key if the key type permits it.

       The caller must have write permission on a key to be able to update it.

       payload  and  plen specify the data for the new payload.  payload may be NULL and plen may be zero if the
       key type permits that.  The key type may reject the data if it's in the wrong format or in some other way
       invalid.

RETURN VALUE

       On  success  keyctl_update() returns 0.  On error, the value -1 will be returned and errno will have been
       set to an appropriate error.

ERRORS

       ENOKEY The key specified is invalid.

       EKEYEXPIRED
              The key specified has expired.

       EKEYREVOKED
              The key specified had been revoked.

       EINVAL The payload data was invalid.

       ENOMEM Insufficient memory to store the new payload.

       EDQUOT The key quota for this user would be exceeded by increasing the size of the key to accommodate the
              new payload.

       EACCES The key exists, but is not writable by the calling process.

       EOPNOTSUPP
              The key type does not support the update operation on its keys.

LINKING

       This  is  a  library  function  that  can  be  found  in libkeyutils.  When linking, -lkeyutils should be
       specified to the linker.

SEE ALSO

       keyctl(1), add_key(2), keyctl(2), request_key(2), keyctl(3), keyrings(7), keyutils(7)