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Action C API

Defines API for querying action and sending action. More...

Attributes​

Name
uint32_tlen
size_tsize

Detailed Description​

Defines API for querying action and sending action.

A EOS.IO action has the following abstract structure:

struct action {
  capi_name  account_name; // the contract defining the primary code to execute for code/type
  capi_name  action_name; // the action to be taken
  permission_level authorization; // the accounts and permission levels provided
  bytes data; // opaque data processed by code
};

This API enables your contract to inspect the fields on the current action and act accordingly.

Example: 

// Assume this action is used for the following examples:
// {
//  "code": "eos",
//  "type": "transfer",
//  "authorization": [{ "account": "inita", "permission": "active" }],
//  "data": {
//    "from": "inita",
//    "to": "initb",
//    "amount": 1000
//  }
// }

char buffer[128];
uint32_t total = read_action(buffer, 5); // buffer contains the content of the action up to 5 bytes
print(total); // Output: 5

uint32_t msgsize = action_size();
print(msgsize); // Output: size of the above action's data field


require_recipient("initc"_n); // initc account will be notified for this action

require_auth("inita"_n); // Do nothing since inita exists in the auth list
require_auth("initb"_n); // Throws an exception

print(current_time()); // Output: timestamp (in microseconds since 1970) of current block

Attributes Documentation​

variable len​

uint32_t len;

variable size​

size_t size;

Updated on 2022-12-05 at 15:38:07 +0000