ComponentExt: Add document to Linux details.

src/traits.rs

@@ -1486,10 +1486,17 @@ pub trait ComponentExt: Debug {
  /// println!("{}°C", component.temperature());
  /// }
  /// ```
+ ///
+ /// ## Linux
+ ///
+ /// Returns `f32::NAN` if it failed to retrieve it.
  fn temperature(&self) -> f32;
 
  /// Returns the maximum temperature of the component (in celsius degree).
  ///
+ /// Note: if `temperature` is higher than the current `max`,
+ /// `max` value will be updated on refresh.
+ ///
  /// ```no_run
  /// use sysinfo::{ComponentExt, System, SystemExt};
  ///
@@ -1498,6 +1505,11 @@ pub trait ComponentExt: Debug {
  /// println!("{}°C", component.max());
  /// }
  /// ```
+ ///
+ /// ## Linux
+ ///
+ /// May be computed by sysinfo from kernel.
+ /// Returns `f32::NAN` if it failed to retrieve it.
  fn max(&self) -> f32;
 
  /// Returns the highest temperature before the component halts (in celsius degree).
@@ -1510,6 +1522,10 @@ pub trait ComponentExt: Debug {
  /// println!("{:?}°C", component.critical());
  /// }
  /// ```
+ ///
+ /// ## Linux
+ ///
+ /// Critical threshold defined by chip or kernel.
  fn critical(&self) -> Option<f32>;
 
  /// Returns the label of the component.
@@ -1522,6 +1538,19 @@ pub trait ComponentExt: Debug {
  /// println!("{}", component.label());
  /// }
  /// ```
+ ///
+ /// ## Linux
+ ///
+ /// Since components informations are retrieved thanks to `hwmon`,
+ /// the labels are generated as follows.
+ /// Note: it may change and it was inspired by `sensors` own formatting.
+ ///
+ /// | name | label | device_model | id_sensor | Computed label by `sysinfo` |
+ /// |---------|--------|------------|----------|----------------------|
+ /// | ✓ | ✓ | ✓ | ✓ | `"{name} {label} {device_model} temp{id}"` |
+ /// | ✓ | ✓ | ✗ | ✓ | `"{name} {label} {id}"` |
+ /// | ✓ | ✗ | ✓ | ✓ | `"{name} {device_model}"` |
+ /// | ✓ | ✗ | ✗ | ✓ | `"{name} temp{id}"` |
  fn label(&self) -> &str;
 
  /// Refreshes component.