> For the complete documentation index, see [llms.txt](https://contracts.synapseprotocol.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://contracts.synapseprotocol.com/elin/contracts/utils/reentrancyguard.md).

# ReentrancyGuard

*Contract module that helps prevent reentrant calls to a function. Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier available, which can be applied to functions to make sure there are no nested (reentrant) calls to them. Note that because there is a single `nonReentrant` guard, functions marked as `nonReentrant` may not call one another. This can be worked around by making those functions `private`, and then adding `external`* *`nonReentrant` entry points to them. TIP: If you would like to learn more about reentrancy and alternative ways to protect against it, check out our blog post <https://blog.openzeppelin.com/reentrancy-after-istanbul/\\[Reentrancy> After Istanbul].*