# dns-checker
CLI tool to check domain liveness via DNS lookups and emit JSON results.
## Usage
```bash
cargo run -- --input urls.txt --output results.json
```
## Options
- `--backend` DNS resolver backend (`hickory` default, `gnu-c` Linux only).
- `--concurrency` Maximum concurrent DNS checks (default: 100).
## Python bindings
Python 3.10+ bindings for the Rust library using PyO3.
## Build (maturin)
```bash
maturin develop --release --features "python gnu-c"
# or
maturin build --release --features "python gnu-c"
```
## Backends
- `hickory` (default)
- `gnu-c` (Linux only): build with `--features "python gnu-c"`
## Usage
```python
import dns_checker
dns_checker.run("links.txt", "results.json", backend="hickory", concurrency=100)
# or using the gnu-c backend (Linux only)
dns_checker.run("links.txt", "results.json", backend="gnu-c", concurrency=100)
```