---
name: "TSConfig"
section: "3ts"
platform: "linux"
package: "trafficserver-dev"
version: "9.2.5+ds-0+deb12u4"
release: "Debian 12 (Bookworm)"
platforms: ["linux"]
url: "https://new.carta.tech/TSConfig"
---

# TSConfig(3ts)

TSConfig API function

## NAME

TSConfig Functions - TSConfig API function

## SYNOPSIS

```
#include <ts/ts.h>
```

- **typedef void (\*TSConfigDestroyFunc)(void\*)**

  - **unsigned int TSConfigSet(unsigned int id, void \*data, *TSConfigDestroyFunc* funcp)**

  - ***TSConfig* TSConfigGet(unsigned int id)**

  - **void TSConfigRelease(unsigned int id, *TSConfig* configp)**

  - **void \*TSConfigDataGet(*TSConfig* configp)**

  ## DESCRIPTION

These functions provide a mechanism to safely update configurations for a plugin.

If a plugin stores its configuration in a data structure, updating that structure due to changes in the configuration file can be dangerous due to the asynchronous nature of plugin callbacks. To avoid that problem these functions allow a plugin to register a configuration and then later replace it with another instance without changing the instance in use by plugin callbacks. This works in the same manner as *shared pointer*. When a plugin needs to access the configuration data, it calls *TSConfigGet()* which returns a pointer that will remain valid until the plugin calls *TSConfigRelease()*. The configuration instance is updated with *TSConfigSet()* which will update an internal pointer but will not change any instance in use via *TSConfigGet()*. When the last in use pointer is released, the old configuration is destructed using the function passed to func:*TSConfigSet*. This handles the overlapping configuration update case correctly.

Initialization is done with *TSConfigSet()*. The *id* should be zero on the first call. This will allocate a slot for the configuration, which is returned. Subsequent calls must use this value. If the *id* is not zero, that value is returned. In general, the code will look something like

```
class Config { ... }; // Configuration data.
int Config_Id = 0;
//...
void ConfigUpdate() {
   Config* cfg = new Config;
   cfg.load(); // load config...
   Config_Id = TSConfigSet(Config_Id, cfg,
      [](void* cfg){delete static_cast<Config*>(config);});
}
//...
PluginInit() {
   // ...
   ConfigUpdate();
   // ...
}
```

**Config\_Id** is a global variable holding the configuration id, which is updated by the return value of *TSConfigSet()*.

The configuration instance is retrieved with *TSConfigGet()*. This returns a wrapper class from which the configuration can be extracted with *TSConfigDataGet()*. The wrapper is used to release the configuration instance when it is no longer in use. The code in a callback tends to look like

```
int callback() {
   auto cfg_ref = TSConfigGet(Config_Id);
   Config* cfg = static_cast<Config*>(TSConfigDataGet(cfg_ref));
   // ... use cfg
   TSConfigRelease(Config_Id, cfg_ref);
}
```

## COPYRIGHT

2026, dev@trafficserver.apache.org