diff --git a/Cargo.lock b/Cargo.lock
index 2ac962772..d78a65543 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -374,6 +374,11 @@ dependencies = [
  "termcolor 1.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "exitcode"
+version = "1.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "failure"
 version = "0.1.5"
@@ -1166,6 +1171,7 @@ dependencies = [
  "crc 1.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "crc32fast 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "digest 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "exitcode 1.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "flame 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "flamer 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "flate2 1.0.11 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2055,6 +2061,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum either 1.5.2 (registry+https://github.com/rust-lang/crates.io-index)" = "5527cfe0d098f36e3f8839852688e63c8fff1c90b2b405aef730615f9a7bcf7b"
 "checksum ena 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f56c93cc076508c549d9bb747f79aa9b4eb098be7b8cad8830c3137ef52d1e00"
 "checksum env_logger 0.6.2 (registry+https://github.com/rust-lang/crates.io-index)" = "aafcde04e90a5226a6443b7aabdb016ba2f8307c847d524724bd9b346dd1a2d3"
+"checksum exitcode 1.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "de853764b47027c2e862a995c34978ffa63c1501f2e15f987ba11bd4f9bba193"
 "checksum failure 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "795bd83d3abeb9220f257e597aa0080a508b27533824adf336529648f6abf7e2"
 "checksum failure_derive 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "ea1063915fd7ef4309e222a5a07cf9c319fb9c7836b1f89b85458672dbb127e1"
 "checksum fake-simd 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "e88a8acf291dafb59c2d96e8f59828f3838bb1a70398823ade51a84de6a6deed"
diff --git a/vm/Cargo.toml b/vm/Cargo.toml
index d6f872e0a..2ded048f5 100644
--- a/vm/Cargo.toml
+++ b/vm/Cargo.toml
@@ -71,6 +71,9 @@ flamer = { version = "0.3", optional = true }
 [target.'cfg(all(unix, not(any(target_os = "android", target_os = "redox"))))'.dependencies]
 pwd = "1"
 
+[target.'cfg(unix)'.dependencies]
+exitcode = "1.1.2"
+
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 crc32fast = "1.2.0"
 adler32 = "1.0.3"
diff --git a/vm/src/stdlib/os.rs b/vm/src/stdlib/os.rs
index e4cde6256..6c9a892a7 100644
--- a/vm/src/stdlib/os.rs
+++ b/vm/src/stdlib/os.rs
@@ -11,6 +11,8 @@ use std::os::windows::fs::OpenOptionsExt;
 use std::time::{Duration, SystemTime};
 use std::{env, fs};
 
+#[cfg(unix)]
+use exitcode;
 #[cfg(unix)]
 use nix::errno::Errno;
 #[cfg(all(unix, not(target_os = "redox")))]
@@ -1292,6 +1294,22 @@ fn extend_module_platform_specific(vm: &VirtualMachine, module: PyObjectRef) ->
         "SEEK_SET" => ctx.new_int(Whence::SeekSet as i8),
         "SEEK_CUR" => ctx.new_int(Whence::SeekCur as i8),
         "SEEK_END" => ctx.new_int(Whence::SeekEnd as i8),
+        "EX_OK" => ctx.new_int(exitcode::OK as i8),
+        "EX_USAGE" => ctx.new_int(exitcode::USAGE as i8),
+        "EX_DATAERR" => ctx.new_int(exitcode::DATAERR as i8),
+        "EX_NOINPUT" => ctx.new_int(exitcode::NOINPUT as i8),
+        "EX_NOUSER" => ctx.new_int(exitcode::NOUSER as i8),
+        "EX_NOHOST" => ctx.new_int(exitcode::NOHOST as i8),
+        "EX_UNAVAILABLE" => ctx.new_int(exitcode::UNAVAILABLE as i8),
+        "EX_SOFTWARE" => ctx.new_int(exitcode::SOFTWARE as i8),
+        "EX_OSERR" => ctx.new_int(exitcode::OSERR as i8),
+        "EX_OSFILE" => ctx.new_int(exitcode::OSFILE as i8),
+        "EX_CANTCREAT" => ctx.new_int(exitcode::CANTCREAT as i8),
+        "EX_IOERR" => ctx.new_int(exitcode::IOERR as i8),
+        "EX_TEMPFAIL" => ctx.new_int(exitcode::TEMPFAIL as i8),
+        "EX_PROTOCOL" => ctx.new_int(exitcode::PROTOCOL as i8),
+        "EX_NOPERM" => ctx.new_int(exitcode::NOPERM as i8),
+        "EX_CONFIG" => ctx.new_int(exitcode::CONFIG as i8),
     });
 
     #[cfg(not(target_os = "redox"))]