crabgrind 0.2.5

Rust bindings to "Valgrind Client Request" interface
Documentation 
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Resets the profile counters to zero

Immediately clears all event counters (instruction fetches, cache misses, etc.)
without writing a dump file. It is useful for discarding data from setup phases
or previous iterations in a benchmarking loop.

# Example

Clearing setup costs to isolate some operation:

```rust
use crabgrind::callgrind;
use std::collections::HashMap;
use std::ffi::CStr;

let mut map:HashMap<u8, u8> = HashMap::with_capacity(1024);
let reason = CStr::from_bytes_with_nul(b"HashMap::insert\0").unwrap();

// Reset counters to ignore initialization overhead
callgrind::zero_stats();

// Perform operation we want to measure
map.insert(0, 0);

// Dump isolated data
callgrind::dump_stats(reason);
```

> Run with Callgrind
>
> ```text
> :~$ valgrind --tool=callgrind target/debug/zero_stats
> ```
>
> ```text
> --666538--   Zeroing costs...
> --666538--   ...done
> --666538-- Start dumping at BB 223561 (Client Request: HashMap::insert)...
> --666538-- Dump to ./callgrind.out.666538.2
> --666538-- Dumping done.
> ```

## Note

Requires Valgrind **3.2** or higher.