print errors to stderr

src/main.rs

@@ -76,17 +76,17 @@ fn main() {
     };
 
     if let Err(ref e) = app::main(opts) {
+        use std::io::prelude::*;
+        let stderr = std::io::stderr();
+        let mut lock = stderr.lock();
         // Write the top-level error message, then chained errors, then backtrace if available
-        error!("error: {}", e);
+        writeln!(lock, "error: {}", e).expect("error while writing error");
         for e in e.iter().skip(1) {
-            error!("caused by: {}", e);
+            writeln!(lock, "caused by: {}", e).expect("error while writing error");
         }
         if let Some(backtrace) = e.backtrace() {
-            error!("backtrace: {:?}", backtrace);
+            writeln!(lock, "backtrace: {:?}", backtrace).expect("error while writing error");
         }
-
-        // Exit with a nonzero exit code
-        // TODO: Decide how to allow code to set this to something other than 1
         std::process::exit(1);
     }
 }