diff --git a/src/lib.rs b/src/lib.rs
index babd18c..92c4fb5 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -69,15 +69,34 @@ pub mod shell {
         }
     }
 
-    fn process_line(input: &str) -> String {
+    struct CmdOutput {
+        outp: String,
+        rc: i16,
+    }
+
+    impl CmdOutput {
+        fn from_values(output: String, rc: i16) -> CmdOutput {
+            let myoutp = CmdOutput {
+                outp: output,
+                rc: rc,
+            }
+            return myoutp;
+        }
+    }
+
+    fn process_line(input: &str) -> Result<CmdOutput, CmdOutput> {
         let mut commands = input.trim().split("|").peekable();
         let mut previous_command = None;
         let mut resultat = String::new();
 
+        let mut outp = CmdOutput::new_empty();
+
         while let Some(command) = commands.next()  {
             let parts = match shell_words::split(&command.trim()) {
                 Ok(w) => w,
-                Err(e) => { return format!("Error parsing the command : {:?}", e); },
+                Err(e) => { 
+                    return Err(CmdOutput::from_values(format!("Could not parse command {:?}", e), -1));
+                },
             };
             let command = parts[0].as_str();
             let args = Vec::from(&parts[1..]);