Improve documentation for ProcessRefreshKind

src/common.rs

@@ -289,8 +289,9 @@ impl System {
     /// It is the same as calling:
     ///
     /// ```no_run
-    /// # use sysinfo::{ProcessRefreshKind, System};
+    /// # use sysinfo::{Pid, ProcessRefreshKind, System};
     /// # let mut system = System::new();
+    /// # let pid = Pid::from(0);
     /// system.refresh_process_specifics(
     ///     pid,
     ///     ProcessRefreshKind::new()
@@ -1420,6 +1421,12 @@ assert_eq!(r.", stringify!($name), "().is_some(), false);
 
 /// Used to determine what you want to refresh specifically on the [`Process`] type.
 ///
+/// When all refresh are ruled out, a [`Process`] will still retrieve the following information:
+///  * Process ID ([`Pid`])
+///  * Parent process ID
+///  * Process name
+///  * Start time
+///
 /// ⚠️ Just like all other refresh types, ruling out a refresh doesn't assure you that
 /// the information won't be retrieved if the information is accessible without needing
 /// extra computation.
@@ -1498,7 +1505,19 @@ impl ProcessRefreshKind {
         with_disk_usage,
         without_disk_usage
     );
-    impl_get_set!(ProcessRefreshKind, user, with_user, without_user);
+    impl_get_set!(
+        ProcessRefreshKind,
+        user,
+        with_user,
+        without_user,
+        "\
+It will retrieve the following information:
+
+ * user ID
+ * user effective ID (if available on the platform)
+ * user group ID (if available on the platform)
+ * user effective ID (if available on the platform)"
+    );
     impl_get_set!(ProcessRefreshKind, memory, with_memory, without_memory);
     impl_get_set!(ProcessRefreshKind, cwd, with_cwd, without_cwd);
     impl_get_set!(ProcessRefreshKind, root, with_root, without_root);