diff --git a/src/devhost/sdwirec.rs b/src/devhost/sdwirec.rs
index ddbf7eb..945d076 100644
--- a/src/devhost/sdwirec.rs
+++ b/src/devhost/sdwirec.rs
@@ -74,11 +74,7 @@ impl Sdwirec {
         cmd += &self.format_device(chooser);
         cmd += "-u";
 
-        let res = self.try_run(&cmd);
-        if let Err(e) = res {
-            return Err(e);
-        }
-        let res = res.unwrap();
+        let res = self.try_run(&cmd)?;
         if !res.status.success() {
             return Err(Box::new(std::io::Error::new(
                 std::io::ErrorKind::Other,
@@ -96,14 +92,14 @@ impl Sdwirec {
          */
         let res = String::from_utf8(res.stdout).unwrap();
         if res.contains("SD connected to: TS") {
-            return Ok(SdwirecStat::TS);
+            Ok(SdwirecStat::TS)
         } else if res.contains("SD connected to: DUT") {
-            return Ok(SdwirecStat::DUT);
+            Ok(SdwirecStat::DUT)
         } else {
-            return Err(Box::new(std::io::Error::new(
+            Err(Box::new(std::io::Error::new(
                 std::io::ErrorKind::Other,
                 format!("Failed to get status of device. Reason: {}", res),
-            )));
+            )))
         }
     }
 
@@ -116,11 +112,7 @@ impl Sdwirec {
         cmd += &self.format_device(chooser);
         cmd += "-ts";
 
-        let res = self.try_run(&cmd);
-        if let Err(e) = res {
-            return Err(e);
-        }
-        let res = res.unwrap();
+        let res = self.try_run(&cmd)?;
         if !res.status.success() {
             return Err(Box::new(std::io::Error::new(
                 std::io::ErrorKind::Other,
@@ -143,11 +135,7 @@ impl Sdwirec {
         cmd += &self.format_device(chooser);
         cmd += "-d";
 
-        let res = self.try_run(&cmd);
-        if let Err(e) = res {
-            return Err(e);
-        }
-        let res = res.unwrap();
+        let res = self.try_run(&cmd)?;
         if !res.status.success() {
             return Err(Box::new(std::io::Error::new(
                 std::io::ErrorKind::Other,
diff --git a/src/exec/cli_exec.rs b/src/exec/cli_exec.rs
index 4261e74..a9c5b89 100644
--- a/src/exec/cli_exec.rs
+++ b/src/exec/cli_exec.rs
@@ -24,11 +24,7 @@ impl CliTester {
 impl CliTester {
     fn run_command(&mut self, command: &String) -> Result<(), Box<dyn Error>> {
         info!("Write to shell: {}", command);
-        let res = self.inner.write(command.as_bytes());
-        if let Err(e) = res {
-            return Err(e);
-        }
-        Ok(())
+        self.inner.write(command.as_bytes())
     }
 }
 
@@ -81,12 +77,8 @@ impl CliTestApi for CliTester {
         info!("Waiting for string {{{}}}", expected);
         loop {
             sleep(Duration::from_millis(DURATION));
-            let res = self.inner.read();
-            if let Err(e) = res {
-                return Err(e);
-            }
-            let line = res.unwrap();
-            buf.extend_from_slice(&line);
+            let res = self.inner.read()?;
+            buf.extend_from_slice(&res);
             let content = String::from_utf8(buf.clone()).unwrap_or_default();
             if content.contains(expected) {
                 info!("Matched string {{{}}}", expected);
@@ -112,10 +104,7 @@ impl CliTestApi for CliTester {
         cmd += &echo_content_rand;
         cmd += " \n";
 
-        let res = self.run_command(&cmd);
-        if let Err(e) = res {
-            return Err(e);
-        }
+        self.run_command(&cmd)?;
 
         let res = self.wait_serial(&echo_content_rand, timeout);
         if let Err(e) = res {
@@ -124,7 +113,7 @@ impl CliTestApi for CliTester {
             }
             return Err(e);
         }
-        res
+        Ok(())
     }
     fn assert_script_run(&mut self, script: &str, timeout: u32) -> Result<(), Box<dyn Error>> {
         let mut cmd = script.to_owned();
@@ -134,13 +123,10 @@ impl CliTestApi for CliTester {
         cmd += &echo_content_rand;
         cmd += " \n";
 
-        let res = self.run_command(&cmd);
-        if let Err(e) = res {
-            return Err(e);
-        }
+        self.run_command(&cmd)?;
 
-        let res = self.wait_serial(&echo_content_rand, timeout);
-        res
+        self.wait_serial(&echo_content_rand, timeout)?;
+        Ok(())
     }
     fn background_script_run(&mut self, script: &str) -> Result<(), Box<dyn Error>> {
         let mut cmd = script.to_owned();
diff --git a/src/pythonapi/pyexec.rs b/src/pythonapi/pyexec.rs
index 9fc457a..0302f54 100644
--- a/src/pythonapi/pyexec.rs
+++ b/src/pythonapi/pyexec.rs
@@ -65,12 +65,12 @@ impl PyExec {
 
         let timeout = timeout.unwrap_or(30);
 
-        if let Some(_) = inner.downcast_ref::<CliTester>() {
+        if inner.downcast_ref::<CliTester>().is_some() {
             let inner = inner.downcast_mut::<CliTester>().unwrap();
             inner
                 .script_run(script, timeout)
                 .map_err(|e| PyRuntimeError::new_err(e.to_string()))?;
-        } else if let Some(_) = inner.downcast_ref::<SudoCliTester>() {
+        } else if inner.downcast_ref::<SudoCliTester>().is_some() {
             let inner = inner.downcast_mut::<SudoCliTester>().unwrap();
             inner
                 .script_run(script, timeout)
@@ -95,12 +95,12 @@ impl PyExec {
 
         let timeout = timeout.unwrap_or(30);
 
-        if let Some(_) = inner.downcast_ref::<CliTester>() {
+        if inner.downcast_ref::<CliTester>().is_some() {
             let inner = inner.downcast_mut::<CliTester>().unwrap();
             inner
                 .assert_script_run(script, timeout)
                 .map_err(|e| PyRuntimeError::new_err(e.to_string()))?;
-        } else if let Some(_) = inner.downcast_ref::<SudoCliTester>() {
+        } else if inner.downcast_ref::<SudoCliTester>().is_some() {
             let inner = inner.downcast_mut::<SudoCliTester>().unwrap();
             inner
                 .assert_script_run(script, timeout)
@@ -118,12 +118,12 @@ impl PyExec {
         let inner = self_.inner.get_mut()?;
         let inner = inner.as_any_mut();
 
-        if let Some(_) = inner.downcast_ref::<CliTester>() {
+        if inner.downcast_ref::<CliTester>().is_some() {
             let inner = inner.downcast_mut::<CliTester>().unwrap();
             inner
                 .background_script_run(script)
                 .map_err(|e| PyRuntimeError::new_err(e.to_string()))?;
-        } else if let Some(_) = inner.downcast_ref::<SudoCliTester>() {
+        } else if inner.downcast_ref::<SudoCliTester>().is_some() {
             let inner = inner.downcast_mut::<SudoCliTester>().unwrap();
             inner
                 .background_script_run(script)
@@ -141,12 +141,12 @@ impl PyExec {
         let inner = self_.inner.get_mut()?;
         let inner = inner.as_any_mut();
 
-        if let Some(_) = inner.downcast_ref::<CliTester>() {
+        if inner.downcast_ref::<CliTester>().is_some() {
             let inner = inner.downcast_mut::<CliTester>().unwrap();
             inner
                 .writeln(script)
                 .map_err(|e| PyRuntimeError::new_err(e.to_string()))?;
-        } else if let Some(_) = inner.downcast_ref::<SudoCliTester>() {
+        } else if inner.downcast_ref::<SudoCliTester>().is_some() {
             let inner = inner.downcast_mut::<SudoCliTester>().unwrap();
             inner
                 .writeln(script)
@@ -171,12 +171,12 @@ impl PyExec {
 
         let timeout = timeout.unwrap_or(30);
 
-        if let Some(_) = inner.downcast_ref::<CliTester>() {
+        if inner.downcast_ref::<CliTester>().is_some() {
             let inner = inner.downcast_mut::<CliTester>().unwrap();
             inner
                 .wait_serial(expected, timeout)
                 .map_err(|e| PyRuntimeError::new_err(e.to_string()))?;
-        } else if let Some(_) = inner.downcast_ref::<SudoCliTester>() {
+        } else if inner.downcast_ref::<SudoCliTester>().is_some() {
             let inner = inner.downcast_mut::<SudoCliTester>().unwrap();
             inner
                 .wait_serial(expected, timeout)
@@ -201,7 +201,7 @@ impl PyExec {
 
         let timeout = timeout.unwrap_or(30);
 
-        if let Some(_) = inner.downcast_ref::<SudoCliTester>() {
+        if inner.downcast_ref::<SudoCliTester>().is_some() {
             let inner = inner.downcast_mut::<SudoCliTester>().unwrap();
             inner
                 .script_sudo(script, timeout)
@@ -226,7 +226,7 @@ impl PyExec {
 
         let timeout = timeout.unwrap_or(30);
 
-        if let Some(_) = inner.downcast_ref::<SudoCliTester>() {
+        if inner.downcast_ref::<SudoCliTester>().is_some() {
             let inner = inner.downcast_mut::<SudoCliTester>().unwrap();
             inner
                 .assert_script_sudo(script, timeout)
diff --git a/src/pythonapi/pyhook.rs b/src/pythonapi/pyhook.rs
index bd472b3..34695ed 100644
--- a/src/pythonapi/pyhook.rs
+++ b/src/pythonapi/pyhook.rs
@@ -18,10 +18,9 @@ pub fn build_ttyhook(inner: Py<PyAny>) -> PyTty {
     let inner = PyTtyWrapper {
         tty: heap_raw(inner)
     };
-    let res = PyTty {
+    PyTty {
         inner
-    };
-    res
+    }
 }
 
 pub struct PyTtyHook {
diff --git a/src/pythonapi/shell_like.rs b/src/pythonapi/shell_like.rs
index 0ac0020..5a9c07c 100644
--- a/src/pythonapi/shell_like.rs
+++ b/src/pythonapi/shell_like.rs
@@ -231,7 +231,7 @@ impl PyTty {
         let inner = Box::into_inner(inner);
         let inner = inner.into_any();
 
-        if let Some(_) = inner.downcast_ref::<SimpleRecorder>() {
+        if inner.downcast_ref::<SimpleRecorder>().is_some() {
             let inner = inner.downcast::<SimpleRecorder>().unwrap();
             let inner = inner.exit();
             Ok(PyTty {
@@ -239,7 +239,7 @@ impl PyTty {
                     tty: heap_raw(inner),
                 },
             })
-        } else if let Some(_) = inner.downcast_ref::<Asciicast>() {
+        } else if inner.downcast_ref::<Asciicast>().is_some() {
             let inner = inner.downcast::<Asciicast>().unwrap();
             let inner = inner.exit();
             Ok(PyTty {
@@ -247,7 +247,7 @@ impl PyTty {
                     tty: heap_raw(inner),
                 },
             })
-        } else if let Some(_) = inner.downcast_ref::<Tee>() {
+        } else if inner.downcast_ref::<Tee>().is_some() {
             let inner = inner.downcast::<Tee>().unwrap();
             let inner = inner.exit();
             Ok(PyTty {
@@ -255,7 +255,7 @@ impl PyTty {
                     tty: heap_raw(inner),
                 },
             })
-        } else if let Some(_) = inner.downcast_ref::<CliTester>() {
+        } else if inner.downcast_ref::<CliTester>().is_some() {
             let inner = inner.downcast::<CliTester>().unwrap();
             let inner = inner.exit();
             Ok(PyTty {
@@ -263,7 +263,7 @@ impl PyTty {
                     tty: heap_raw(inner),
                 },
             })
-        } else if let Some(_) = inner.downcast_ref::<SudoCliTester>() {
+        } else if inner.downcast_ref::<SudoCliTester>().is_some() {
             let inner = inner.downcast::<SudoCliTester>().unwrap();
             let inner = inner.exit();
             Ok(PyTty {
@@ -284,12 +284,12 @@ impl PyTty {
         let inner = self.inner.get_mut()?;
         let inner = inner.as_any_mut();
 
-        if let Some(_) = inner.downcast_ref::<SimpleRecorder>() {
+        if inner.downcast_ref::<SimpleRecorder>().is_some() {
             let inner = inner.downcast_mut::<SimpleRecorder>().unwrap();
             inner
                 .begin()
                 .map_err(|e| PyRuntimeError::new_err(e.to_string()))
-        } else if let Some(_) = inner.downcast_ref::<Asciicast>() {
+        } else if inner.downcast_ref::<Asciicast>().is_some() {
             let inner = inner.downcast_mut::<Asciicast>().unwrap();
             inner
                 .begin()
@@ -305,12 +305,12 @@ impl PyTty {
         let inner = self.inner.get_mut()?;
         let inner = inner.as_any_mut();
 
-        if let Some(_) = inner.downcast_ref::<SimpleRecorder>() {
+        if inner.downcast_ref::<SimpleRecorder>().is_some() {
             let inner = inner.downcast_mut::<SimpleRecorder>().unwrap();
             inner
                 .end()
                 .map_err(|e| PyRuntimeError::new_err(e.to_string()))
-        } else if let Some(_) = inner.downcast_ref::<Asciicast>() {
+        } else if inner.downcast_ref::<Asciicast>().is_some() {
             let inner = inner.downcast_mut::<Asciicast>().unwrap();
             inner
                 .end()
@@ -326,12 +326,12 @@ impl PyTty {
         let inner = self.inner.get_mut()?;
         let inner = inner.as_any_mut();
 
-        if let Some(_) = inner.downcast_ref::<SimpleRecorder>() {
+        if inner.downcast_ref::<SimpleRecorder>().is_some() {
             let inner = inner.downcast_mut::<SimpleRecorder>().unwrap();
             inner
                 .start()
                 .map_err(|e| PyRuntimeError::new_err(e.to_string()))
-        } else if let Some(_) = inner.downcast_ref::<Asciicast>() {
+        } else if inner.downcast_ref::<Asciicast>().is_some() {
             let inner = inner.downcast_mut::<Asciicast>().unwrap();
             inner
                 .start()
@@ -347,12 +347,12 @@ impl PyTty {
         let inner = self.inner.get_mut()?;
         let inner = inner.as_any_mut();
 
-        if let Some(_) = inner.downcast_ref::<SimpleRecorder>() {
+        if inner.downcast_ref::<SimpleRecorder>().is_some() {
             let inner = inner.downcast_mut::<SimpleRecorder>().unwrap();
             inner
                 .pause()
                 .map_err(|e| PyRuntimeError::new_err(e.to_string()))
-        } else if let Some(_) = inner.downcast_ref::<Asciicast>() {
+        } else if inner.downcast_ref::<Asciicast>().is_some() {
             let inner = inner.downcast_mut::<Asciicast>().unwrap();
             inner
                 .pause()
@@ -368,7 +368,7 @@ impl PyTty {
         let inner = self.inner.get_mut()?;
         let inner = inner.as_any_mut();
 
-        if let Some(_) = inner.downcast_ref::<SimpleRecorder>() {
+        if inner.downcast_ref::<SimpleRecorder>().is_some() {
             let inner = inner.downcast_mut::<SimpleRecorder>().unwrap();
             let target = other.inner.safe_take()?;
             let target = Box::into_inner(target);
@@ -379,7 +379,7 @@ impl PyTty {
             let target = target.unwrap();
             other.inner.tty = heap_raw(target);
             Ok(())
-        } else if let Some(_) = inner.downcast_ref::<Asciicast>() {
+        } else if inner.downcast_ref::<Asciicast>().is_some() {
             let inner = inner.downcast_mut::<Asciicast>().unwrap();
             let target = other.inner.safe_take()?;
             let target = Box::into_inner(target);
@@ -403,7 +403,7 @@ impl PyTty {
         let inner = Box::into_inner(inner);
         let inner = inner.into_any();
 
-        if let Some(_) = inner.downcast_ref::<PyTtyHook>() {
+        if inner.downcast_ref::<PyTtyHook>().is_some() {
             let inner = inner.downcast::<PyTtyHook>().unwrap();
             let res = inner.inner;
             Ok(res)
diff --git a/src/term/asciicast.rs b/src/term/asciicast.rs
index 1abbef7..7e9c1d7 100644
--- a/src/term/asciicast.rs
+++ b/src/term/asciicast.rs
@@ -71,7 +71,7 @@ impl Asciicast {
             }
             let inner = inner.as_mut().unwrap();
             let new_data = inner.read();
-            if let Err(_) = new_data {
+            if new_data.is_err() {
                 return;
             }
             let new_data = new_data.unwrap();
@@ -118,14 +118,14 @@ impl AnyBase for Asciicast {
 impl Tty for Asciicast {
     fn read(&mut self) -> Result<Vec<u8>, Box<dyn Error>> {
         let data = self.data.lock();
-        if let Err(_) = data {
+        if data.is_err() {
             return Err(Box::<dyn Error>::from("Read from Asciicast failed."));
         }
         let mut data = data.unwrap();
         let res = data.clone();
         data.clear();
 
-        return Ok(res);
+        Ok(res)
     }
     fn read_line(&mut self) -> Result<Vec<u8>, Box<dyn Error>> {
         let mut res = Vec::new();
@@ -141,11 +141,11 @@ impl Tty for Asciicast {
                 break;
             }
         }
-        return Ok(res);
+        Ok(res)
     }
     fn write(&mut self, data: &[u8]) -> Result<(), Box<dyn Error>> {
         // let begin = self.begin.lock();
-        // if let Err(_) = begin {
+        // if begin.is_err() {
         //     return Err(Box::<dyn Error>::from("Recorder not started."));
         // }
         // let begin = begin.unwrap();
@@ -172,9 +172,7 @@ impl Tty for Asciicast {
             return Err(Box::<dyn Error>::from("You've already exited."));
         }
         let inner = inner.as_mut().unwrap();
-        let res = inner.write(data);
-
-        res
+        inner.write(data)
     }
 }
 
@@ -182,15 +180,14 @@ impl WrapperTty for Asciicast {
     fn exit(self) -> DynTty {
         let inner = self.inner.clone();
         let mut inner = inner.lock().unwrap();
-        let inner = inner.take().unwrap();
-        inner
+        inner.take().unwrap()
     }
 }
 
 impl Recorder for Asciicast {
     fn begin(&mut self) -> Result<(), Box<dyn Error>> {
         let logged = self.logged.lock();
-        if let Err(_) = logged {
+        if logged.is_err() {
             return Err(Box::<dyn Error>::from("Recorder not started."));
         }
         let mut logged = logged.unwrap();
@@ -198,14 +195,14 @@ impl Recorder for Asciicast {
 
         let time = SystemTime::now();
         let begin_time = self.begin_time.lock();
-        if let Err(_) = begin_time {
+        if begin_time.is_err() {
             return Err(Box::<dyn Error>::from("Recorder not started."));
         }
         let mut begin_time = begin_time.unwrap();
         *begin_time = time;
 
         let begin = self.begin.lock();
-        if let Err(_) = begin {
+        if begin.is_err() {
             return Err(Box::<dyn Error>::from("Recorder not started."));
         }
         let mut begin = begin.unwrap();
@@ -218,7 +215,7 @@ impl Recorder for Asciicast {
 
     fn end(&mut self) -> Result<String, Box<dyn Error>> {
         let begin = self.begin.lock();
-        if let Err(_) = begin {
+        if begin.is_err() {
             return Err(Box::<dyn Error>::from("Recorder not started."));
         }
         let mut begin = begin.unwrap();
@@ -228,7 +225,7 @@ impl Recorder for Asciicast {
         *begin = false;
         let mut res = String::new();
         let logged = self.logged.lock();
-        if let Err(_) = logged {
+        if logged.is_err() {
             return Err(Box::<dyn Error>::from("Recorder not started."));
         }
         let logged = logged.unwrap();
diff --git a/src/term/recorder.rs b/src/term/recorder.rs
index 3e6a684..b73082c 100644
--- a/src/term/recorder.rs
+++ b/src/term/recorder.rs
@@ -1,6 +1,6 @@
 use std::{any::Any, error::Error, mem::replace};
 
-use crate::{consts::SHELL_PROMPT, info, term::tty::Tty, util::anybase::AnyBase};
+use crate::{info, term::tty::Tty, util::anybase::AnyBase};
 
 use super::tty::{DynTty, WrapperTty};
 
@@ -47,45 +47,27 @@ impl AnyBase for SimpleRecorder {
 
 impl Tty for SimpleRecorder {
     fn read(&mut self) -> Result<Vec<u8>, Box<dyn Error>> {
-        let data = self.inner.read();
-        if let Err(e) = data {
-            return Err(e);
-        }
-        let data = data.unwrap();
+        let data = self.inner.read()?;
 
         if self.begin {
             self.logged.extend(data.clone());
         }
 
-        return Ok(data);
+        Ok(data)
     }
     fn read_line(&mut self) -> Result<Vec<u8>, Box<dyn Error>> {
-        let data = self.inner.read_line();
-        if let Err(e) = data {
-            return Err(e);
-        }
-        let data = data.unwrap();
+        let data = self.inner.read_line()?;
 
         if self.begin {
             self.logged.extend(data.clone());
         }
 
-        return Ok(data);
+        Ok(data)
     }
     fn write(&mut self, data: &[u8]) -> Result<(), Box<dyn Error>> {
-        let res = self.inner.write(data);
-        if let Err(e) = res {
-            return Err(e);
-        }
-
-        if self.begin {
-            // For echo back:
-            let line = SHELL_PROMPT.as_bytes();
-            self.logged.extend(line);
-            self.logged.extend(data);
-        }
+        self.inner.write(data)?;
 
-        return Ok(());
+        Ok(())
     }
 }
 
@@ -103,7 +85,7 @@ impl Recorder for SimpleRecorder
 
         info!("Recorder begin to record.");
 
-        return Ok(());
+        Ok(())
     }
 
     fn end(&mut self) -> Result<String, Box<dyn Error>> {
@@ -118,20 +100,20 @@ impl Recorder for SimpleRecorder
 
         info!("Recorder end to record.");
 
-        return Ok(String::from_utf8(logged).unwrap());
+        Ok(String::from_utf8(logged).unwrap())
     }
     fn pause(&mut self) -> Result<(), Box<dyn Error>> {
         self.begin = false;
         info!("Recorder pause for recording...");
-        return Ok(());
+        Ok(())
     }
     fn start(&mut self) -> Result<(), Box<dyn Error>> {
         self.begin = true;
         info!("Recorder continue for recording...");
-        return Ok(());
+        Ok(())
     }
     fn swap(&mut self, target: DynTty) -> Result<DynTty, Box<dyn Error>> {
         let inner = replace(&mut self.inner, target);
-        return Ok(inner);
+        Ok(inner)
     }
 }
diff --git a/src/term/serial.rs b/src/term/serial.rs
index 1259616..503619e 100644
--- a/src/term/serial.rs
+++ b/src/term/serial.rs
@@ -28,9 +28,9 @@ impl Serial {
 
         info!("Serial port opened: {} at baud rate {}", port, baud);
 
-        return Ok(Serial {
+        Ok(Serial {
             inner: inner.unwrap(),
-        });
+        })
     }
 }
 
@@ -109,6 +109,6 @@ impl Tty for Serial {
             }
         }
 
-        return Ok(());
+        Ok(())
     }
 }
diff --git a/src/term/shell.rs b/src/term/shell.rs
index 7769335..1e8f262 100644
--- a/src/term/shell.rs
+++ b/src/term/shell.rs
@@ -1,5 +1,5 @@
 use ptyprocess::{stream::Stream, PtyProcess};
-use std::io::{BufRead, BufReader, Read};
+use std::io::BufReader;
 use std::ops::DerefMut;
 use std::os::fd::AsRawFd;
 use std::{
@@ -26,20 +26,13 @@ pub struct Shell {
 }
 
 impl Shell {
-    /**
-     * This implementation method is DEFINITELY needs to be changed in the future,
-     * at least need to use a stty to let shell HAPPY.
-     * But for now... Well, it works.
-     * I've already spent too much time trying to make this thing work... Just move on.
-     * For now.
-     */
     pub fn build(shell: Option<&str>) -> Result<Shell, Box<dyn Error>> {
         let shell = shell.unwrap_or("/bin/sh");
 
         info!("Spawn shell process: {}", shell);
 
         let mut inner = Command::new(shell);
-        inner.args(&["-i"]);
+        inner.args(["-i"]);
         let inner = PtyProcess::spawn(inner);
         if let Err(e) = inner {
             err!("Failed to spawn shell process. Reason: {}", e);
@@ -144,7 +137,7 @@ impl Tty for Shell {
         if !res.is_empty() {
             log!("Shell read: {:?}", String::from_utf8_lossy(&res));
         }
-        return Ok(res);
+        Ok(res)
     }
     fn read_line(&mut self) -> Result<Vec<u8>, Box<dyn Error>> {
         let mut res = Vec::new();
@@ -167,20 +160,20 @@ impl Tty for Shell {
                 break;
             }
         }
-        return Ok(res);
+        Ok(res)
     }
     fn write(&mut self, data: &[u8]) -> Result<(), Box<dyn Error>> {
         let mut stream = self.inner.lock().unwrap();
         info!("Shell locked...");
-        match stream.write(data) {
+        match stream.write_all(data) {
             Ok(_) => {
                 stream.flush().unwrap();
                 info!("Shell write: {:?}", String::from_utf8_lossy(data));
-                return Ok(());
+                Ok(())
             }
             Err(e) => {
                 err!("Write to shell process failed. Reason: {}", e);
-                return Err(Box::new(e));
+                Err(Box::new(e))
             }
         }
     }
diff --git a/src/term/ssh.rs b/src/term/ssh.rs
index 130fb8e..ebfedb1 100644
--- a/src/term/ssh.rs
+++ b/src/term/ssh.rs
@@ -190,6 +190,6 @@ impl Tty for Ssh {
             err!("Flush to shell process failed. Reason: {}", e);
             return Err(Box::<dyn Error>::from(e));
         }
-        return Ok(());
+        Ok(())
     }
 }
diff --git a/src/util/logger.rs b/src/util/logger.rs
index c219bf3..f8b94dd 100644
--- a/src/util/logger.rs
+++ b/src/util/logger.rs
@@ -12,47 +12,47 @@ pub enum LogLevel {
 singleton!(LogLevelConf, i32, LogLevel::Info as i32);
 
 pub fn __log(s: &str) {
-    if LogLevelConf::get().to_owned() <= LogLevel::Debug as i32 {
+    if *LogLevelConf::get() <= LogLevel::Debug as i32 {
         println!("{} {}", "[LOG]".blue(), s);
     }
 }
 
 #[macro_export]
 macro_rules! log {
-    ($($arg:tt)*) => (crate::util::logger::__log(&format!($($arg)*)))
+    ($($arg:tt)*) => ($crate::util::logger::__log(&format!($($arg)*)))
 }
 
 pub fn __info(s: &str) {
-    if LogLevelConf::get().to_owned() <= LogLevel::Info as i32 {
+    if *LogLevelConf::get() <= LogLevel::Info as i32 {
         println!("{} {}", "[INFO]".green(), s);
     }
 }
 
 #[macro_export]
 macro_rules! info {
-    ($($arg:tt)*) => (crate::util::logger::__info(&format!($($arg)*)))
+    ($($arg:tt)*) => ($crate::util::logger::__info(&format!($($arg)*)))
 }
 
 pub fn __warn(s: &str) {
-    if LogLevelConf::get().to_owned() <= LogLevel::Warn as i32 {
+    if *LogLevelConf::get() <= LogLevel::Warn as i32 {
         eprintln!("{} {}", "[WARN]".yellow(), s);
     }
 }
 
 #[macro_export]
 macro_rules! warn {
-    ($($arg:tt)*) => (crate::util::logger::__warn(&format!($($arg)*)))
+    ($($arg:tt)*) => ($crate::util::logger::__warn(&format!($($arg)*)))
 }
 
 pub fn __err(s: &str) {
-    if LogLevelConf::get().to_owned() <= LogLevel::Error as i32 {
+    if *LogLevelConf::get() <= LogLevel::Error as i32 {
         eprintln!("{} {}", "[ERROR]".red(), s);
     }
 }
 
 #[macro_export]
 macro_rules! err {
-    ($($arg:tt)*) => (crate::util::logger::__err(&format!($($arg)*)))
+    ($($arg:tt)*) => ($crate::util::logger::__err(&format!($($arg)*)))
 }
 
 pub fn set_log_level(level: LogLevel) {
diff --git a/src/util/util.rs b/src/util/util.rs
index da40eb1..8d79f74 100644
--- a/src/util/util.rs
+++ b/src/util/util.rs
@@ -20,12 +20,10 @@ macro_rules! unfinished {
 }
 
 pub fn rand_string(len: usize) -> Vec<u8> {
-    let rnd = thread_rng()
+    thread_rng()
         .sample_iter(&Alphanumeric)
         .take(len)
-        .collect::<Vec<u8>>();
-
-    rnd
+        .collect::<Vec<u8>>()
 }
 
 pub fn try_read<R: BufRead + ?Sized>(