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src/ffi.md

@@ -23,20 +23,23 @@ libc = "0.2.0"
 
 ## Prepare the build script
 
-Because [snappy](https://github.com/google/snappy) is a static library by default. So there is no C++ std linked in the output artifact. In order to use this foreign library in Rust, we have to manually specify that we want to link stdc++ in our project. The easiest way to do this is by setting up a build script.
+Because [snappy](https://github.com/google/snappy) is a static library by default.
+So there is no C++ std linked in the output artifact. 
+n order to use this foreign library in Rust, we have to manually specify that we want to link stdc++ in our project.
+The easiest way to do this is by setting up a build script.
 
-First edit `Cargo.toml`, inside `package` add `build = "build.rs"`.
+First edit `Cargo.toml`, inside `package` add `build = "build.rs"`:
 ```toml
 [package]
 ...
 build = "build.rs"
 ```
 
-Then create a new file at the root of your workspace, named `build.rs`.
+Then create a new file at the root of your workspace, named `build.rs`:
 ```rust
 // build.rs
 fn main() {
-    println!("cargo:rustc-link-lib=dylib=stdc++");
+    println!("cargo:rustc-link-lib=dylib=stdc++"); // This line may be unnecessary for some environment.
     println!("cargo:rustc-link-search=<YOUR SNAPPY LIBRARY PATH>");
 }
 ```