diff --git a/src/bin/thin_check.rs b/src/bin/thin_check.rs
index 1c1ea27..2298ce9 100644
--- a/src/bin/thin_check.rs
+++ b/src/bin/thin_check.rs
@@ -25,14 +25,12 @@ fn main() {
         .arg(
             Arg::with_name("SB_ONLY")
                 .help("Only check the superblock.")
-                .long("super-block-only")
-                .value_name("SB_ONLY"),
+                .long("super-block-only"),
         )
         .arg(
             Arg::with_name("SKIP_MAPPINGS")
                 .help("Don't check the mapping tree")
-                .long("skip-mappings")
-                .value_name("SKIP_MAPPINGS"),
+                .long("skip-mappings"),
         )
         .arg(
             Arg::with_name("AUTO_REPAIR")
@@ -47,7 +45,7 @@ fn main() {
         .arg(
             Arg::with_name("CLEAR_NEEDS_CHECK")
                 .help("Clears the 'needs_check' flag in the superblock")
-                .long("clear-needs-check"),
+                .long("clear-needs-check-flag"),
         )
         .arg(
             Arg::with_name("OVERRIDE_MAPPING_ROOT")
diff --git a/tests/cache_check.rs b/tests/cache_check.rs
index 3faddb5..8cf716c 100644
--- a/tests/cache_check.rs
+++ b/tests/cache_check.rs
@@ -42,7 +42,7 @@ fn accepts_help() -> Result<()> {
 #[test]
 fn missing_metadata() -> Result<()> {
     let stderr = run_fail(cache_check!())?;
-    assert!(stderr.contains("No input file provided"));
+    assert!(stderr.contains(msg::MISSING_INPUT_ARG));
     Ok(())
 }
 
@@ -66,7 +66,7 @@ fn unreadable_metadata() -> Result<()> {
     let md = mk_valid_md(&mut td)?;
     cmd!("chmod", "-r", &md).run()?;
     let stderr = run_fail(cache_check!(&md))?;
-    assert!(stderr.contains("syscall 'open' failed: Permission denied"));
+    assert!(stderr.contains("Permission denied"));
     Ok(())
 }
 
diff --git a/tests/common/mod.rs b/tests/common/mod.rs
index 67debcc..f47347f 100644
--- a/tests/common/mod.rs
+++ b/tests/common/mod.rs
@@ -18,6 +18,22 @@ use test_dir::TestDir;
 
 //------------------------------------------
 
+#[cfg(not(feature = "rust_tests"))]
+pub mod msg {
+    pub const FILE_NOT_FOUND: &str = "Couldn't stat file";
+    pub const MISSING_INPUT_ARG: &str = "No input file provided";
+    pub const MISSING_OUTPUT_ARG: &str = "No output file provided";
+}
+
+#[cfg(feature = "rust_tests")]
+pub mod msg {
+    pub const FILE_NOT_FOUND: &str = "Couldn't find input file";
+    pub const MISSING_INPUT_ARG: &str = "The following required arguments were not provided";
+    pub const MISSING_OUTPUT_ARG: &str = "The following required arguments were not provided";
+}
+
+//------------------------------------------
+
 #[macro_export]
 macro_rules! path_to_cpp {
     ($name: literal) => {
diff --git a/tests/thin_delta.rs b/tests/thin_delta.rs
index acdee59..2d570de 100644
--- a/tests/thin_delta.rs
+++ b/tests/thin_delta.rs
@@ -65,6 +65,7 @@ fn snap2_unspecified() -> Result<()> {
 #[test]
 fn dev_unspecified() -> Result<()> {
     let stderr = run_fail(thin_delta!("--snap1", "45", "--snap2", "46"))?;
-    assert!(stderr.contains("No input device provided"));
+    // TODO: replace with msg::MISSING_INPUT_ARG once the rust version is ready
+    assert!(stderr.contains("No input file provided"));
     Ok(())
 }
diff --git a/tests/thin_repair.rs b/tests/thin_repair.rs
index 74eef8e..e0b6529 100644
--- a/tests/thin_repair.rs
+++ b/tests/thin_repair.rs
@@ -53,6 +53,7 @@ fn missing_input_file() -> Result<()> {
     let md = mk_zeroed_md(&mut td)?;
     let stderr = run_fail(thin_repair!("-i", "no-such-file", "-o", &md))?;
     assert!(superblock_all_zeroes(&md)?);
+    // TODO: replace with msg::FILE_NOT_FOUND once the rust version is ready
     assert!(stderr.contains("Couldn't stat file"));
     Ok(())
 }
@@ -72,6 +73,7 @@ fn missing_output_file() -> Result<()> {
     let mut td = TestDir::new()?;
     let md = mk_valid_md(&mut td)?;
     let stderr = run_fail(thin_repair!("-i", &md))?;
+    // TODO: replace with msg::MISSING_OUTPUT_ARG once the rust version is ready
     assert!(stderr.contains("No output file provided."));
     Ok(())
 }
diff --git a/tests/thin_restore.rs b/tests/thin_restore.rs
index f1d82fa..b5aa434 100644
--- a/tests/thin_restore.rs
+++ b/tests/thin_restore.rs
@@ -44,7 +44,7 @@ fn no_input_file() -> Result<()> {
     let mut td = TestDir::new()?;
     let md = mk_zeroed_md(&mut td)?;
     let stderr = run_fail(thin_restore!("-o", &md))?;
-    assert!(stderr.contains("No input file provided."));
+    assert!(stderr.contains(msg::MISSING_INPUT_ARG));
     Ok(())
 }
 
@@ -54,7 +54,7 @@ fn missing_input_file() -> Result<()> {
     let md = mk_zeroed_md(&mut td)?;
     let stderr = run_fail(thin_restore!("-i", "no-such-file", "-o", &md))?;
     assert!(superblock_all_zeroes(&md)?);
-    assert!(stderr.contains("Couldn't stat file"));
+    assert!(stderr.contains(msg::FILE_NOT_FOUND));
     Ok(())
 }
 
@@ -73,7 +73,7 @@ fn no_output_file() -> Result<()> {
     let mut td = TestDir::new()?;
     let xml = mk_valid_xml(&mut td)?;
     let stderr = run_fail(thin_restore!("-i", &xml))?;
-    assert!(stderr.contains("No output file provided."));
+    assert!(stderr.contains(msg::MISSING_OUTPUT_ARG));
     Ok(())
 }
 
diff --git a/thin-provisioning/thin_delta.cc b/thin-provisioning/thin_delta.cc
index 56f97fa..71eeb3d 100644
--- a/thin-provisioning/thin_delta.cc
+++ b/thin-provisioning/thin_delta.cc
@@ -687,7 +687,7 @@ thin_delta_cmd::run(int argc, char **argv)
 	}
 
 	if (argc == optind)
-		die("No input device provided.");
+		die("No input file provided.");
 	else
 		fs.dev = argv[optind];