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|text= [[remoteExec]] and [[remoteExecCall]] are currently filtered by BattlEye's remoteexec.txt, the string analyzed by BE is formatted the same way as the following example's output: | |text= [[remoteExec]] and [[remoteExecCall]] are currently filtered by BattlEye's remoteexec.txt, the string analyzed by BE is formatted the same way as the following example's output: | ||
<code>[[format]] ["%1 %2", functionName, [[str]] params]</code> | <code>[[format]] ["%1 %2", functionName, [[str]] params]</code> | ||
If [[CfgRemoteExec]] {{hl|class Functions}} is set to | If [[CfgRemoteExec]] {{hl|class Functions}} is set to {{hl|c= mode = 1;}}, the following remoteexec.txt exclusion can be used to safely allow all whitelisted *_fnc_* functions taking an array as parameter to go through: | ||
<code>!="\w+?_fnc_\w+? \[<nowiki/>[\S\s]*\]"</code> | <code>!="\w+?_fnc_\w+? \[<nowiki/>[\S\s]*\]"</code> | ||
Any attempt to exploit this exclusion using other RE methods like [[createUnit]] will run into "Error Missing ;" without any malicious code being executed. Mod makers should refrain from remote-executing raw commands from clients, as they require individual exclusions, and instead use *_fnc_* functions taking an array as parameter, which are covered by the above exclusion. | Any attempt to exploit this exclusion using other RE methods like [[createUnit]] will run into "Error Missing ;" without any malicious code being executed. Mod makers should refrain from remote-executing raw commands from clients, as they require individual exclusions, and instead use *_fnc_* functions taking an array as parameter, which are covered by the above exclusion. |
Revision as of 00:20, 16 November 2021
Description
- Description:
- Asks the server to execute the given function or script command on the given target machine(s).
- Functions are executed in the scheduled environment; suspension is allowed.
- Script commands are executed in the unscheduled environment; suspension is not allowed (see Example 7).
- Multiplayer:
- Remote executions are queued and are therefore executed in the same order on remote clients (see Example 8).
- Groups:
- Multiplayer
Syntax
- Syntax:
- params remoteExec [order, targets, JIP]
- Parameters:
- params: Anything - order's parameter
- order: String - Function or command name; while any function or command can be used here, only those allowed by CfgRemoteExec will actually be executed
- targets (Optional, default: 0):
- Number (See also Machine network ID):
- 0: the order will be executed globally, i.e. on the server and every connected client, including the machine where remoteExec originated
- 2: the order will only be executed on the server
- Other number: the order will be executed on the machine where clientOwner matches the given number
- Negative number: the effect is inverted: -2 means every client but not the server, -12 means the server and every client, except for the client where clientOwner returns 12
- Object - The order will be executed where the given object is local
- String - Interpreted as an Identifier (variable name). The function / command will be executed where the object or group identified by the variable with the provided name is local
- Side - The order will be executed on machines where the player is on the specified side
- Group - The order will be executed on machines where the player is in the specified group
- Array - Array of any combination of the types listed above
- Number (See also Machine network ID):
- JIP (Optional, default: false):
- Boolean - If true, a unique JIP ID is generated and the remoteExec statement is added to the JIP queue from which it will be executed for every JIP
- String:
- If the string is empty, it is interpreted as false
- If the string is in format "Number:Number" (e.g. "0:0"), it is interpreted as a netId (see below)
- Else the string is treated as a custom JIP ID and the remoteExec statement is added to the JIP queue, replacing statements that have the same JIP ID
- Object, Group or netId - The persistent execution of the remoteExec statement is attached to the given object or group.
When the object / group is deleted, the remoteExec statement is automatically removed from the JIP queue
See also Example 3 on how to remove statements from the JIP queue. - Return Value:
Alternative Syntax
- Syntax:
- remoteExec [functionName, targets, JIP]
- Parameters:
- functionName: String - See the main syntax above for more details.
- targets (Optional, default: 0): Number, Object, String, Side, Group or Array - See the main syntax above for more details.
- JIP (Optional, default: false): Boolean, String, Object, Group or netId - See the main syntax above for more details.
- Return Value:
- nil or String - See the main syntax above for more details.
Examples
- Example 1:
- How to write remoteExec/remoteExecCall:
hint "Hello"; // becomes ["Hello"] remoteExec ["hint"]; "Hello" remoteExec ["hint"]; // alternatively
unit1 setFace "Miller"; // becomes [unit1, "Miller"] remoteExec ["setFace"];
cutRsc ["", "BLACK OUT"]; // becomes [["", "BLACK OUT"]] remoteExec ["cutRsc"]; // double brackets are needed as the unary command takes an array
// functions, however, do not need double squared brackets ["line 1", "line 2"] spawn BIS_fnc_infoText; // becomes ["line 1", "line 2"] remoteExec ["BIS_fnc_infoText"];
- Example 2:
- send an order to specific machines:
"message" remoteExec ["hint", 0]; // sends a hint message to everyone, identical to
"message" remoteExec ["hint"]
"message" remoteExec ["hint", -2]; // sends a hint message to everybody but the server "message" remoteExec ["hint", myCar]; // sends a hint message where myCar is local "message" remoteExec ["hint", -clientOwner]; // sends a hint message to everybody but the current machine - Example 3:
- Add statements to the JIP queue:
private _jipId = ["mission state: the car is broken"] remoteExec ["systemChat", 0, true]; // adds the hint to the JIP queue and returns the JIP queue order id waitUntil { canMove _car }; remoteExec ["", _jipId]; // the systemChat order is removed from the JIP queue
["mission state: the car is broken"] remoteExec ["systemChat", 0, _queueObject]; // ... remoteExec ["", _queueObject]; // the order attached to _queueObject is removed
private _jipId = ["mission state: the car is broken"] remoteExec ["systemChat", 0, "MY_JIP_ID"]; // _jipId is actually "MY_JIP_ID" now waitUntil { canMove _car }; ["mission state: the car is repaired"] remoteExec ["systemChat", 0, "MY_JIP_ID"]; // this order replaces the previous one // ... remoteExec ["", "MY_JIP_ID"]; // the "MY_JIP_ID" order is removed from the JIP queue
- Example 4:
- Some more complex examples:
["Open", true] remoteExec ["BIS_fnc_arsenal", MyTargetPlayer]; [MyCurator, [[MyObject1, MyObject2], false]] remoteExec ["addCuratorEditableObjects", 2];
- Example 5:
- A tricky example: executing
player setAmmo [primaryWeapon player, 1];
(on machines where the player is in MyGroup):[player, [primaryWeapon player, 1]] remoteExec ["setAmmo", MyGroup]; // WRONG: the local player object is used here! { player setAmmo [primaryWeapon player, 1]; } remoteExec ["call", MyGroup]; // CORRECT: the remote player object is used here
- Example 6:
- Multiplayer Scripting "performance trick"
This[0, -2] select isDedicated
check is worth to avoid function server-side calculations only:["message"] remoteExec ["BIS_fnc_infoText"]; // not ideal - the function will still run on the dedicated server for nothing ["message"] remoteExec ["BIS_fnc_infoText", [0, -2] select isDedicated]; // ideal - the dedicated server will not run the code, a player-hosted server will "message" remoteExec ["hint", [0, -2] select isDedicated]; // the check is too costy to be worthy "message" remoteExec ["hint"]; // the (dedicated) server will automatically ditch hint usage due to it not having an interface
- Example 7:
- As said in the description: commands will be executed in an unscheduled environment
[{ sleep 1 }] remoteExec ["call"]; // will throw an error: it is forbidden to use sleep (or waitUntil, etc) in unscheduled environment
- Example 8:
"Message 1" remoteExec ["systemChat"]; "Message 2" remoteExec ["systemChat"]; // will result in // "Message 1" // "Message 2" // in this exact order on clients
Additional Information
- See also:
- remoteExecCall remoteExecutedOwner isRemoteExecuted isRemoteExecutedJIP Arma 3: Remote Execution canSuspend BIS_fnc_MP
Notes
-
Report bugs on the Feedback Tracker and/or discuss them on the Arma Discord or on the Forums.
Only post proven facts here! Add Note
- Posted on Dec 29, 2015 - 20:28 (UTC)
-
remoteExec and remoteExecCall are currently filtered by BattlEye's remoteexec.txt, the string analyzed by BE is formatted the same way as the following example's output:
format ["%1 %2", functionName, str params]
If CfgRemoteExec class Functions is set to mode = 1;, the following remoteexec.txt exclusion can be used to safely allow all whitelisted *_fnc_* functions taking an array as parameter to go through:!="\w+?_fnc_\w+? \[[\S\s]*\]"
Any attempt to exploit this exclusion using other RE methods like createUnit will run into "Error Missing ;" without any malicious code being executed. Mod makers should refrain from remote-executing raw commands from clients, as they require individual exclusions, and instead use *_fnc_* functions taking an array as parameter, which are covered by the above exclusion.
- Posted on Jan 30, 2017 - 18:35 (UTC)
-
[some params] remoteExec ['some command',2,true];
will fail, as you can't use JIP and remoteExec on server only[some params] remoteExec ['some command',2]; // works
- Posted on Apr 22, 2018 - 15:29 (UTC)
-
It seems that only global functions can be executed, as opposed to local.
params remoteExec ["fnc_someScriptedFunction", targets, JIP]; // works
params remoteExec ["_fnc_someScriptedFunction", targets, JIP]; // does not work
- Posted on Mar 05, 2021 - 00:48 (UTC)
-
The remoteExec'ed function only has to exist on the target machine. For example:
// initPlayerLocal.sqf TAG_fnc_testRemote = { hint "Remote Exec Received"; };
// Execute on dedicated server: [] remoteExec ["TAG_fnc_testRemote", -2];
Will display a hint for every client. This is especially useful for when the server is running a mod that is not required by clients.