1 files changed, 7 insertions, 1 deletions
diff --git a/src/nix.rs b/src/nix.rs
index e59ceaed..3cc5beff 100644
--- a/src/nix.rs
+++ b/src/nix.rs
@@ -1,7 +1,7 @@
 use libc;
 use std;
 
-use errno::Errno;
+use errno::{Errno, EINVAL};
 
 pub type NixResult<T> = Result<T, NixError>;
 
@@ -11,6 +11,12 @@ pub enum NixError {
     InvalidPath
 }
 
+impl NixError {
+    pub fn invalid_argument() -> NixError {
+        NixError::Sys(EINVAL)
+    }
+}
+
 pub trait NixPath {
     fn with_nix_path<T, F>(&self, f: F) -> Result<T, NixError>
         where F: FnOnce(*const libc::c_char) -> T;