# hv_vcpu_get_reg(_:_:_:) Gets the current value of a vCPU register. ``` func hv_vcpu_get_reg(_ vcpu: hv_vcpu_t, _ reg: hv_reg_t, _ value: UnsafeMutablePointer) -> hv_return_t ``` ## Parameters `vcpu` The vCPU instance. `reg` The ID of the general register. `value` The value of the register `reg` on output. ## Return Value [`HV_SUCCESS`](/documentation/Hypervisor/HV_SUCCESS) if the operation was successful, otherwise an error code specified in [`hv_return_t`](/documentation/Hypervisor/hv_return_t). ## Discussion > Important: > This function must be called by the owning thread. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)