> 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/ida-9.5/ida-actions/hx_addvararg.md).

# hx\_AddVarArg

## Description

Add an argument of a variadic call.

It is impossible to detect the correct number of variadic arguments in all cases, so the decompiler may detect too few arguments. This command allows you to correct such cases by increasing the number of arguments.

It is available only when the cursor is located on a call to a variadic function (like `printf`). The decompiler automatically detects the argument locations, the user can only increase or decrease their number.

**Hotkeys**:

* <kbd>Numpad+ Add variadic argument</kbd>

This command is useful if the decompiler determines the number of arguments incorrectly.

For example:

```
        printf("This is a test call: %d\n");
```

apparently lacks an argument. Pressing <kbd>Numpad+ modifies it:</kbd>

```
        printf("This is a test call: %d\n", v1);
```


---

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