throwTo: mention interruptible foreign calls

diff --git a/GHC/Conc/Sync.lhs b/GHC/Conc/Sync.lhs
index cc16853..9b7415d 100644 (file)
--- a/GHC/Conc/Sync.lhs
+++ b/GHC/Conc/Sync.lhs
@@ -274,7 +274,10 @@ another thread.
 If the target thread is currently making a foreign call, then the
 exception will not be raised (and hence 'throwTo' will not return)
 until the call has completed.  This is the case regardless of whether
 If the target thread is currently making a foreign call, then the
 exception will not be raised (and hence 'throwTo' will not return)
 until the call has completed.  This is the case regardless of whether

-the call is inside a 'mask' or not.
+the call is inside a 'mask' or not.  However, in GHC a foreign call
+can be annotated as @interruptible@, in which case a 'throwTo' will
+cause the RTS to attempt to cause the call to return; see the GHC
+documentation for more details.

 
 Important note: the behaviour of 'throwTo' differs from that described in
 the paper \"Asynchronous exceptions in Haskell\"
 
 Important note: the behaviour of 'throwTo' differs from that described in
 the paper \"Asynchronous exceptions in Haskell\"