> 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/9.0sp1/developer-guide/idc/idc-api-reference/alphabetical-list-of-idc-functions/709.md).

# update\_extra\_cmt

```
Set or update extra comment line
     ea   - linear address
     n    - number of additional line (0..MAX_ITEM_LINES)
     line - the line to display
IDA displays additional lines from number 0 up to the first unexisting
additional line. So, if you specify additional line #150 and there is no
additional line #149, your line will not be displayed.
MAX_ITEM_LINES is defined in IDA.CFG
To set anterior  line #n use (E_PREV + n)
To set posterior line #n use (E_NEXT + n)

void update_extra_cmt(long ea, long n, string line);
```


---

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