> For the complete documentation index, see [llms.txt](https://docs.hex-rays.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.hex-rays.com/8.4/developer-guide/idc/idc-api-reference/alphabetical-list-of-idc-functions/710.md).

# Functions provided by the replayer debugger

```
// Step back in the currently replayed trace
// Returns: error code (0 if none happened).

success step_back();

// Set the current event number, changing the PC register.
// Input  : the event to move to
// Events are numbered in reverse order, i.e. 0 is the last available event.
// Returns: error code.

success set_current_tev(long event);

// Get the current event number.
// Returns: the current event number.

long get_current_tev();
```


---

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