CKB Syscalls for Script

A collection of CKB-VM syscalls. Also include relevant constant, such as return codes, sources, Cell fields, header fields, and input fields.

CKB-VM Syscalls

VM Ver.	Syscall ID	C Function Name	Rust Function Name	Description
1	93	ckb_exit	exit	Immediately terminate the execution of the currently running Script and exit with the specified return code.
1	2061	ckb_load_tx_hash	load_tx_hash	Calculate the hash of the current transaction and copy it using partial loading.
1	2051	ckb_load_transaction	load_transaction	Serialize the full transaction of the running Script using the Molecule Encoding 1 format and copy it using partial loading.
1	2062	ckb_load_script_hash	load_script_hash	Calculate the hash of currently running Script and copy it using partial loading.
1	2052	ckb_load_script	load_script	Serialize the currently running Script using the Molecule Encoding 1 format and copy it using partial loading.
1	2071	ckb_load_cell	load_cell	Serialize the specified Cell in the current transaction using the Molecule Encoding 1 format and copy it using partial loading.
1	2081	ckb_load_cell_by_field	load_cell_by_field	Load a single field from the specified Cell in the current transaction and copy it using partial loading.
1	2092	ckb_load_cell_data	load_cell_data	Load the data from the Cell data field in the specified Cell from the current transaction and copy it using partial loading.
1	2091	ckb_load_cell_data_as_code	load_cell_code	Load the data from the Cell data field in the specified Cell from the current transaction, mark the loaded memory page as executable, and copy it using partial loading. The loaded code can then be executed by CKB-VM at a later time.
1	2073	ckb_load_input	load_input	Serialize the specified input Cell in the current transaction using the Molecule Encoding 1 format and copy it using partial loading.
1	2083	ckb_load_input_by_field	load_input_by_field	Load a single field from the specified input Cell in the current transaction and copy it using partial loading.
1	2072	ckb_load_header	load_header	Serialize the specified header associated with an input Cell, dep Cell, or header dep using the Molecule Encoding 1 format and copy it using partial loading.
1	2082	ckb_load_header_by_field	load_header_by_field	Load a single field from the specified header associated with an input Cell, dep Cell, or header dep and copy it using partial loading.
1	2074	ckb_load_witness	load_witness	Load the specified witness in the current transaction and copy it using partial loading.
1	2177	ckb_debug	debug	Print the specified message in CKB's terminal output for the purposes of debugging.
2	2041	ckb_vm_version	vm_version	Return the version of CKB-VM being used to execute the current Script.
2	2042	ckb_current_cycles	current_cycles	Return the number of cycles consumed by the currently running Script immediately before executing this syscall. This syscall will consume an additional 500 cycles.
2	2043	ckb_exec	exec	Run a Script executable from the specified Cell using the current VM context. This replaces the original calling running Script executable with the new specified Script executable. This is similar to the exec call found in several operating systems.
2	2101	ckb_spawn	spawn	Run a Script executable from the specified Cell using the current VM context, but return to the original calling Script executable upon termination. This is similar to the spawn function found in several operating systems and programming languages.
2	2102	ckb_get_memory_limit	get_memory_limit	Return the maximum amount of memory available to the current Script being executed.
2	2105	ckb_current_memory	current_memory	Get the Current Memory Usage. The result is the sum of the memory usage of the parent Script and the child Script.｜
2	2103	ckb_set_content	set_content	Set the content of the designated memory region that can be read by the parent (calling) Script which executed the current Script via the spawn function.
2	2104	ckb_load_extension	load_block_extension	Load the extension field data and copy it using partial loading.

Constants

Return Codes

These are the return codes used by the CKB-VM syscalls.

Const No.	C Example	Description
0	CKB_SUCCESS	No error.
1	CKB_INDEX_OUT_OF_BOUND	Index out of bound. (e.g. No such input Cell.)
2	CKB_ITEM_MISSING	The requested resource does not exist.
3	CKB_LENGTH_NOT_ENOUGH	The supplied memory buffer too small.
4	CKB_INVALID_DATA	The data provided is invalid.

Source

These are the sources for syscalls that query the transaction for input Cells, output Cells, dep Cells, and header deps.

Const No.	C Example	Description
0x1	CKB_SOURCE_INPUT	All input Cells in the transaction.
0x0100000000000001	CKB_SOURCE_GROUP_INPUT	Only the input Cells in the transaction using the same Script as currently running Script.
2	CKB_SOURCE_OUTPUT	All output Cells in the transaction.
0x0100000000000002	CKB_SOURCE_GROUP_OUTPUT	Only the output Cells in the transaction using the same Script as currently running Script.
3	CKB_SOURCE_CELL_DEP	All dep Cells in the transaction.
4	CKB_SOURCE_HEADER_DEP	All header deps in the transaction.

Cell Fields

These are the field specifiers for syscalls that request a specific field of a cell.

Const No.	C Example	Description
0	CKB_CELL_FIELD_CAPACITY	The capacity (CKB) contained in the Cell.
1	CKB_CELL_FIELD_DATA_HASH	The hash of the data within the data field of the Cell.
2	CKB_CELL_FIELD_LOCK	The Lock Script of the Cell.
3	CKB_CELL_FIELD_LOCK_HASH	The hash of the Lock Script of the Cell.
4	CKB_CELL_FIELD_TYPE	The Type Script of the Cell.
5	CKB_CELL_FIELD_TYPE_HASH	The hash of the Type Script of the Cell.
6	CKB_CELL_FIELD_OCCUPIED_CAPACITY	The amount of capacity (CKB) that is currently being used by the Cell.

Header Fields

These are the field specifiers for syscalls that request a specific field of a header dep.

Const No.	C Example	Description
0	CKB_HEADER_FIELD_EPOCH_NUMBER	The epoch number for the header dep.
1	CKB_HEADER_FIELD_EPOCH_START_BLOCK_NUMBER	The block number of first block in the epoch for the header dep.
2	CKB_HEADER_FIELD_EPOCH_LENGTH	The length of the epoch for the header dep.

Input Fields

These are the field specifiers for syscalls that request a specific field of an input Cell.

Const No.	C Example	Description
0	CKB_INPUT_FIELD_OUT_POINT	The out point of the specified input Cell.
1	CKB_INPUT_FIELD_SINCE	The since value of the specified input Cell.