keyctl_clear - Clear a keyring
long keyctl_clear(key_serial_t keyring);
keyctl_clear() clears the contents of a keyring.
The caller must have write permission on a keyring to be able clear it.
On success keyctl_clear() returns 0. On error, the value -1 will be
returned and errno will have been set to an appropriate error.
ENOKEY The keyring specified is invalid.
The keyring specified has expired.
The keyring specified had been revoked.
EACCES The keyring exists, but is not writable by the calling process.
This is a library function that can be found in libkeyutils. When
linking, -lkeyutils should be specified to the linker.