> 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/9.0/developer-guide/idc/idc-api-reference/alphabetical-list-of-idc-functions/713.md).

# patch\_byte

```
Change value of a program byte
If debugger was active then the debugged process memory will be patched too
     ea    - linear address
     value - new value of the byte
Returns: 1 if the database has been modified,
         0 if either the debugger is running and the process' memory
           has value 'value' at address 'ea',
           or the debugger is not running, and the IDB
           has value 'value' at address 'ea already.

success patch_byte(long ea, long value);
```


---

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