auto merge of #13315 : alexcrichton/rust/libc, r=alexcrichton,me

Rebasing of #12526 with a very obscure bug fixed on windows.

src/doc/guide-ffi.md

@@ -12,7 +12,8 @@ The following is a minimal example of calling a foreign function which will
 compile if snappy is installed:
 
 ~~~~ {.ignore}
-use std::libc::size_t;
+extern crate libc;
+use libc::size_t;
 
 #[link(name = "snappy")]
 extern {
@@ -44,7 +45,8 @@ keeping the binding correct at runtime.
 The `extern` block can be extended to cover the entire snappy API:
 
 ~~~~ {.ignore}
-use std::libc::{c_int, size_t};
+extern crate libc;
+use libc::{c_int, size_t};
 
 #[link(name = "snappy")]
 extern {
@@ -402,7 +404,7 @@ global state. In order to access these variables, you declare them in `extern`
 blocks with the `static` keyword:
 
 ~~~{.ignore}
-use std::libc;
+extern crate libc;
 
 #[link(name = "readline")]
 extern {
@@ -420,7 +422,7 @@ interface. To do this, statics can be declared with `mut` so rust can mutate
 them.
 
 ~~~{.ignore}
-use std::libc;
+extern crate libc;
 use std::ptr;
 
 #[link(name = "readline")]
@@ -444,11 +446,15 @@ calling foreign functions. Some foreign functions, most notably the Windows API,
 conventions. Rust provides a way to tell the compiler which convention to use:
 
 ~~~~
+extern crate libc;
+
 #[cfg(target_os = "win32", target_arch = "x86")]
 #[link(name = "kernel32")]
 extern "stdcall" {
-    fn SetEnvironmentVariableA(n: *u8, v: *u8) -> std::libc::c_int;
+    fn SetEnvironmentVariableA(n: *u8, v: *u8) -> libc::c_int;
 }
+
+# fn main() { }
 ~~~~
 
 This applies to the entire `extern` block. The list of supported ABI constraints

src/doc/guide-unsafe.md

@@ -192,7 +192,8 @@ As an example, we give a reimplementation of owned boxes by wrapping
 reimplementation is as safe as the built-in `~` type.
 
 ```
-use std::libc::{c_void, size_t, malloc, free};
+extern crate libc;
+use libc::{c_void, size_t, malloc, free};
 use std::mem;
 use std::ptr;
 

src/doc/index.md

@@ -36,6 +36,7 @@ li {list-style-type: none; }
 * [The `glob` file path matching library](glob/index.html)
 * [The `green` M:N runtime library](green/index.html)
 * [The `hexfloat` library for hexadecimal floating-point literals](hexfloat/index.html)
+* [The `libc` bindings](libc/index.html)
 * [The `native` 1:1 threading runtime](native/index.html)
 * [The `num` arbitrary precision numerics library](num/index.html)
 * [The `rand` library for random numbers and distributions](rand/index.html)

src/doc/rust.md

@@ -1471,11 +1471,13 @@ with the exception that they may not have a body
 and are instead terminated by a semicolon.
 
 ~~~~
-# use std::libc::{c_char, FILE};
+extern crate libc;
+use libc::{c_char, FILE};
 
 extern {
     fn fopen(filename: *c_char, mode: *c_char) -> *FILE;
 }
+# fn main() {}
 ~~~~
 
 Functions within external blocks may be called by Rust code,