man: Document return value of event source prepare callback (#4834)

[elogind.git] / man / sd_event_source_set_prepare.xml

diff --git a/man/sd_event_source_set_prepare.xml b/man/sd_event_source_set_prepare.xml
index 9c78ccd1de9e62d1b5726fffbc2c71fd1fc17d64..f0c8e6c4251747f8439a77a8b12aa4b962c08417 100644 (file)
--- a/man/sd_event_source_set_prepare.xml
+++ b/man/sd_event_source_set_prepare.xml
@@ -76,10 +76,11 @@
     specified as <parameter>callback</parameter> will be invoked
     immediately before the event loop goes to sleep to wait for
     incoming events. It is invoked with the user data pointer passed
-    when the event source was created. The callback function may be
-    used to reconfigure the precise events to wait for. If the
-    <parameter>callback</parameter> parameter is passed as NULL the
-    callback function is reset. </para>
+    when the event source was created. The event source will be disabled
+    if the callback function returns a negative error code. The callback
+    function may be used to reconfigure the precise events to wait for.
+    If the <parameter>callback</parameter> parameter is passed as NULL
+    the callback function is reset. </para>
 
     <para>Event source objects have no preparation callback associated
     when they are first created with calls such as