# **Shmap**
**A key-value store based on unix shared-memory files (shm) for persisting state across program restarts.**
## Features
- Items are stored in the unix shared memory: it uses `shm_open` to create file in the ramdisk (/dev/shm), then they are mapped in memory with mmap.
- Concurrent access to items it provided thanks to `named-lock` mutexes.
- Value serialization can be made transparently with serde (`bincode`), so don't forget to use [serde_bytes](https://crates.io/crates/serde_bytes) to enable optimized handling of `&[u8]` and `Vec<u8>` !
- You can protect your data with AES256-GCM encryption.
- You can add a TTL so that your items won't be available anymore after this timeout.
## Example
```rust
use shmap::{Shmap, ShmapError};
use std::time::Duration;
fn main() -> Result<(), ShmapError> {
let shmap = Shmap::new();
shmap.insert("key", "value")?;
let value = shmap.get("key")?;
assert_eq!(Some("value".to_string()), value);
// It is strongly advised to use TTL to avoid using too much RAM
shmap.insert_with_ttl("key", "temporary_value", Duration::from_secs(60))?;
Ok(())
}
```