KEYCTL\_LINK(3) Linux Key Management Calls KEYCTL\_LINK(3) # [NAME](#NAME) keyctl\_link, keyctl\_unlink - link/unlink a key to/from a keyring # [SYNOPSIS](#SYNOPSIS) ``` #include long keyctl_link(key_serial_t key, key_serial_t keyring); long keyctl_unlink(key_serial_t key, key_serial_t keyring); ``` # [DESCRIPTION](#DESCRIPTION) **keyctl\_link**() creates a link from *keyring* to *key*, displacing any link to another key of the same type and description in that keyring if one exists. **keyctl\_unlink**() removes the link from *keyring* to *key* if it exists. The caller must have **write** permission on a keyring to be able to create or remove links in it. The caller must have **link** permission on a key to be able to create a link to it. # [RETURN VALUE](#RETURN_VALUE) On success **keyctl\_link**() and **keyctl\_unlink**() return **0**. On error, the value **-1** will be returned and *errno* will have been set to an appropriate error. # [ERRORS](#ERRORS) [**ENOKEY**](#ENOKEY) The key or the keyring specified are invalid. [**EKEYEXPIRED**](#EKEYEXPIRED) The key or the keyring specified have expired. [**EKEYREVOKED**](#EKEYREVOKED) The key or the keyring specified have been revoked. [**EACCES**](#EACCES) The keyring exists, but is not **writable** by the calling process. For **keyctl\_link**() only: [**ENOMEM**](#ENOMEM) Insufficient memory to expand the keyring [**EDQUOT**](#EDQUOT) Expanding the keyring would exceed the keyring owner's quota. [**EACCES**](#EACCES~2) The key exists, but is not **linkable** by the calling process. # [LINKING](#LINKING) This is a library function that can be found in *libkeyutils*. When linking, **-lkeyutils** should be specified to the linker. # [SEE ALSO](#SEE_ALSO) [**keyctl**(1)](/man/os/keyutils/keyctl.1), [**add\_key**(2)](/man/os/keyutils/add_key.2), [**keyctl**(2)](/man/os/keyutils/keyctl.2), [**request\_key**(2)](/man/os/keyutils/request_key.2), [**keyctl**(3)](/man/os/keyutils/keyctl.3), [**keyrings**(7)](/man/os/keyutils/keyrings.7), [**keyutils**(7)](/man/os/keyutils/keyutils.7) 4 May 2006 Linux --- Document: keyctl_unlink(3) from keyutils 1.6.3-r41 (Chainguard OS) Source: https://kernel.googlesource.com/pub/scm/linux/kernel/git/dhowells/keyutils.git