Make it work on env opened with WRITEMAP

Author: Kerollmops

heed/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "heed"
-version = "0.22.1-nested-rtxns-2"
+version = "0.22.1-nested-rtxns-3"
 authors = ["Kerollmops <[email protected]>"]
 description = "A fully typed LMDB (mdb.master) wrapper with minimum overhead"
 license = "MIT"
@@ -16,7 +16,7 @@ byteorder = { version = "1.5.0", default-features = false }
 heed-traits = { version = "0.20.0", path = "../heed-traits" }
 heed-types = { version = "0.21.0", default-features = false, path = "../heed-types" }
 libc = "0.2.175"
-lmdb-master-sys = { version = "0.2.6-nested-rtxns", path = "../lmdb-master-sys" }
+lmdb-master-sys = { version = "0.2.6-nested-rtxns-3", path = "../lmdb-master-sys" }
 once_cell = "1.21.3"
 page_size = "0.6.0"
 serde = { version = "1.0.223", features = ["derive"], optional = true }

heed/examples/nested-rtxns.rs

@@ -1,14 +1,16 @@
 use heed::types::*;
-use heed::{Database, EnvOpenOptions};
+use heed::{Database, EnvFlags, EnvOpenOptions};
 use rand::prelude::*;
 use rayon::prelude::*;
 use roaring::RoaringBitmap;
 
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     let dir = tempfile::tempdir()?;
     let env = unsafe {
-        EnvOpenOptions::new()
-            .read_txn_without_tls()
+        let mut options = EnvOpenOptions::new().read_txn_without_tls();
+        #[cfg(not(windows))]
+        options.flags(EnvFlags::WRITE_MAP);
+        options
             .map_size(2 * 1024 * 1024 * 1024) // 2 GiB
             .open(dir.path())?
     };

lmdb-master-sys/Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "lmdb-master-sys"
 # NB: When modifying, also modify html_root_url in lib.rs
-version = "0.2.6-nested-rtxns"
+version = "0.2.6-nested-rtxns-3"
 authors = [
     "Kerollmops <[email protected]>",
     "Dan Burkert <[email protected]>",