A mechanism for programs to return data to the caller after CPI, introduced in v1.10. Programs call `set_return_data(data)` (max 1,024 bytes), and the caller retrieves it with `get_return_data()`. This enables CPI callers to receive structured results without parsing logs or modifying shared accounts.
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A mechanism for programs to return data to the caller after CPI, introduced in v1.10. Programs call `set_return_data(data)` (max 1,024 bytes), and the caller retrieves it with `get_return_data()`. This enables CPI callers to receive structured results without parsing logs or modifying shared accounts.
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Return Data (set_return_data) (return-data) Category: Programming Model Definition: A mechanism for programs to return data to the caller after CPI, introduced in v1.10. Programs call `set_return_data(data)` (max 1,024 bytes), and the caller retrieves it with `get_return_data()`. This enables CPI callers to receive structured results without parsing logs or modifying shared accounts. Related: Cross-Program Invocation (CPI), Program
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A mechanism for one program to call another program's instructions during execution. CPIs enable composability—e.g., a DeFi program can call the Token Program to transfer tokens. CPI depth is limited to 4 levels. The caller passes accounts and instruction data, and the callee runs with the same transaction context.
Executable code deployed on-chain, equivalent to a smart contract on other blockchains. Programs are stateless—they store no data themselves but read/write data in separate accounts they own. Programs are compiled to SBF bytecode and loaded via the BPF Loader. Every program has a unique Program ID (its account's public key).
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The byte array stored in an account that holds program-specific state. Data is typically serialized using Borsh and must be explicitly allocated at account creation. The maximum data size is 10MB. Programs are responsible for defining and managing their own data layout, including discriminators for type identification.
The account that stores the actual SBF ELF bytecode for an upgradeable program. It is separate from the program's main account (which just points to the program data). This separation allows the bytecode to be swapped during upgrades while the program ID stays the same. The program data account also stores the upgrade authority pubkey.
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A mechanism for one program to call another program's instructions during execution. CPIs enable composability—e.g., a DeFi program can call the Token Program to transfer tokens. CPI depth is limited to 4 levels. The caller passes accounts and instruction data, and the callee runs with the same transaction context.
Executable code deployed on-chain, equivalent to a smart contract on other blockchains. Programs are stateless—they store no data themselves but read/write data in separate accounts they own. Programs are compiled to SBF bytecode and loaded via the BPF Loader. Every program has a unique Program ID (its account's public key).
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The fundamental data storage unit on Solana. Every piece of state is stored in an account identified by a 32-byte public key. Accounts hold a lamport balance, an owner program, a data byte array (up to 10MB), and an executable flag. Only the owning program can modify an account's data, but anyone can credit lamports to it.
Executable code deployed on-chain, equivalent to a smart contract on other blockchains. Programs are stateless—they store no data themselves but read/write data in separate accounts they own. Programs are compiled to SBF bytecode and loaded via the BPF Loader. Every program has a unique Program ID (its account's public key).
A single operation within a transaction that invokes a program. An instruction specifies: (1) the program ID to call, (2) an array of account metas (pubkey, is_signer, is_writable), and (3) an opaque data byte array. Programs decode the instruction data to determine which operation to perform.
An atomic unit of execution containing one or more instructions, a recent blockhash, and one or more signatures. All instructions in a transaction execute sequentially and atomically—if any instruction fails, the entire transaction reverts. Transactions have a 1,232-byte size limit (matching IPv6 MTU) and a default 200,000 CU budget.