solana_program/sysvar/last_restart_slot.rs
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//! Information about the last restart slot (hard fork).
//!
//! The _last restart sysvar_ provides access to the last restart slot kept in the
//! bank fork for the slot on the fork that executes the current transaction.
//! In case there was no fork it returns _0_.
//!
//! [`LastRestartSlot`] implements [`Sysvar::get`] and can be loaded efficiently without
//! passing the sysvar account ID to the program.
//!
//! See also the Solana [SIMD proposal][simd].
//!
//! [simd]: https://github.com/solana-foundation/solana-improvement-documents/blob/main/proposals/0047-syscall-and-sysvar-for-last-restart-slot.md
//!
//! # Examples
//!
//! Accessing via on-chain program directly:
//!
//! ```no_run
//! # use solana_program::{
//! # account_info::{AccountInfo, next_account_info},
//! # entrypoint::ProgramResult,
//! # msg,
//! # pubkey::Pubkey,
//! # sysvar::Sysvar,
//! # last_restart_slot::LastRestartSlot,
//! # };
//!
//! fn process_instruction(
//! program_id: &Pubkey,
//! accounts: &[AccountInfo],
//! instruction_data: &[u8],
//! ) -> ProgramResult {
//!
//! let last_restart_slot = LastRestartSlot::get();
//! msg!("last restart slot: {:?}", last_restart_slot);
//!
//! Ok(())
//! }
//! ```
//!
pub use crate::last_restart_slot::LastRestartSlot;
use crate::{impl_sysvar_get, program_error::ProgramError, sysvar::Sysvar};
crate::declare_sysvar_id!(
"SysvarLastRestartS1ot1111111111111111111111",
LastRestartSlot
);
impl Sysvar for LastRestartSlot {
impl_sysvar_get!(sol_get_last_restart_slot);
}