diff --git a/src/io.rs b/src/io.rs
index 05bdc3356..70642438b 100644
--- a/src/io.rs
+++ b/src/io.rs
@@ -1,6 +1,4 @@
 use std::collections::HashMap;
-use std::fs::File;
-use std::io::Read;
 
 /// IOLoad represents current system block devices IO statistics
 #[derive(Debug)]
@@ -45,24 +43,30 @@ impl IOLoad {
     ///
     /// # Notes
     ///
-    /// Current don't support non-unix operating system
+    /// Currently not supported outside Unix. On those operating systems, this
+    /// method always returns an empty map.
     #[cfg(not(unix))]
-    pub fn snapshot() -> HashMap<String, NICLoad> {
+    pub fn snapshot() -> HashMap<String, Self> {
         HashMap::new()
     }
 
     /// Returns the current IO statistics
+    ///
+    /// # Notes
+    ///
+    /// Currently not supported outside Unix. On those operating systems, this
+    /// method always returns an empty map.
     #[cfg(unix)]
-    pub fn snapshot() -> HashMap<String, IOLoad> {
+    pub fn snapshot() -> HashMap<String, Self> {
         let mut result = HashMap::new();
         // https://www.kernel.org/doc/Documentation/block/stat.txt
         if let Ok(dir) = std::fs::read_dir("/sys/block/") {
             for entry in dir {
                 if let Ok(entry) = entry {
                     let stat = entry.path().join("stat");
-                    let mut s = String::new();
-                    if let Err(_) = File::open(stat).and_then(|mut f| f.read_to_string(&mut s)) {
-                        continue;
+                    let s = match std::fs::read_to_string(stat) {
+                        Ok(s) => s,
+                        Err(_) => continue,
                     };
                     let parts = s
                         .split_whitespace()
@@ -71,7 +75,7 @@ impl IOLoad {
                     if parts.len() != 11 {
                         continue;
                     }
-                    let load = IOLoad {
+                    let load = Self {
                         read_io: parts[0],
                         read_merges: parts[1],
                         read_sectors: parts[2],
diff --git a/src/net.rs b/src/net.rs
index 878c6648b..b103da631 100644
--- a/src/net.rs
+++ b/src/net.rs
@@ -32,15 +32,21 @@ impl NICLoad {
     ///
     /// # Notes
     ///
-    /// Current don't support non-unix operating system
+    /// Currently not supported outside Unix. On those operating systems, this
+    /// method always returns an empty map.
     #[cfg(not(unix))]
-    pub fn snapshot() -> HashMap<String, NICLoad> {
+    pub fn snapshot() -> HashMap<String, Self> {
         HashMap::new()
     }
 
     /// Returns the current network interfaces card statistics
+    ///
+    /// # Notes
+    ///
+    /// Currently not supported outside Unix. On those operating systems, this
+    /// method always returns an empty map.
     #[cfg(unix)]
-    pub fn snapshot() -> HashMap<String, NICLoad> {
+    pub fn snapshot() -> HashMap<String, Self> {
         let mut result = HashMap::new();
         if let Ok(dir) = std::fs::read_dir("/sys/class/net/") {
             for entry in dir {
@@ -53,7 +59,7 @@ impl NICLoad {
                             .parse()
                             .unwrap_or_default()
                     };
-                    let load = NICLoad {
+                    let load = Self {
                         rx_bytes: read("rx_bytes"),
                         tx_bytes: read("tx_bytes"),
                         rx_packets: read("rx_packets"),
diff --git a/src/windows/processor.rs b/src/windows/processor.rs
index 5b99f23eb..6df2dc04c 100644
--- a/src/windows/processor.rs
+++ b/src/windows/processor.rs
@@ -289,6 +289,7 @@ pub fn get_key_used(p: &mut Processor) -> &mut Option<KeyHandler> {
     &mut p.key_used
 }
 
+/// get_cpu_frequency returns the CPU frequency in MHz
 pub fn get_cpu_frequency() -> u64 {
     // TODO: support windows
     0