X-Git-Url: https://code.octet-stream.net/netwatcher/blobdiff_plain/244781f32194c2498ef0e3b8225a9ff9791624af..325d5d14560f2190818d6826366dfe88d3857302:/src/lib.rs

diff --git a/src/lib.rs b/src/lib.rs
index 7a8298e..cb3a117 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -43,7 +43,7 @@ impl Interface {
 }
 
 /// Information delivered via callback when a network interface change is detected.
-/// 
+///
 /// This contains up-to-date information about all interfaces, plus a diff which
 /// details which interfaces and IP addresses have changed since the last callback.
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -122,29 +122,38 @@ impl List {
 }
 
 /// A handle to keep alive as long as you wish to receive callbacks.
-/// 
+///
 /// If the callback is executing at the time the handle is dropped, drop will block until
 /// the callback is finished and it's guaranteed that it will not be called again.
-/// 
+///
 /// Do not drop the handle from within the callback itself. It will probably deadlock.
 pub struct WatchHandle {
     _inner: watch::WatchHandle,
 }
 
 /// Retrieve information about all enabled network interfaces and their IP addresses.
-/// 
+///
 /// This is a once-off operation. If you want to detect changes over time, see `watch_interfaces`.
 pub fn list_interfaces() -> Result<HashMap<IfIndex, Interface>, Error> {
     list::list_interfaces().map(|list| list.0)
 }
 
 /// Retrieve interface information and watch for changes, which will be delivered via callback.
-/// 
+///
 /// If setting up the watch is successful, this returns a `WatchHandle` which must be kept for
 /// as long as the provided callback should operate.
-/// 
+///
 /// The callback will fire once immediately with an initial interface list, and a diff as if
 /// there were originally no interfaces present.
-pub fn watch_interfaces<F: FnMut(Update) + 'static>(callback: F) -> Result<WatchHandle, Error> {
+///
+/// This function will return an error if there is a problem configuring the watcher, or if there
+/// is an error retrieving the initial interface list.
+///
+/// We assume that if listing the interfaces worked the first time, then it will continue to work
+/// for as long as the watcher is running. If listing interfaces begins to fail later, those
+/// failures will be swallowed and the callback will not be called for that change event.
+pub fn watch_interfaces<F: FnMut(Update) + Send + 'static>(
+    callback: F,
+) -> Result<WatchHandle, Error> {
     watch::watch_interfaces(callback).map(|handle| WatchHandle { _inner: handle })
 }