> 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/185.md).

# strstr

```
Search a substring in a string
     str    - input string
     substr - substring to search
     icase  - is case-insensitive search?
returns: 0..n - index in the 'str' where the substring starts
         -1   - if the substring is not found
Thread-safe function.

long strstr(string str, string substr, bool icase=false);
#define stristr(str, substr) strstr((str), (substr), 1)
```


---

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