Document @cast module search paths

2 files changed, 11 insertions, 4 deletions

diff --git a/NEWS b/NEWS
index 7670f681..4a65bacb 100644
--- a/NEWS
+++ b/NEWS
@@ -1,5 +1,10 @@
 * What's new
 
+- Typecasting with @cast now supports modules search paths, which is
+  useful in case there are multiple places where the type definition
+  may be found.  For example:
+    @cast(sdev, "scsi_device", "kernel:scsi_mod")->sdev_state
+
 - On-file flight recorder is supported. It allows stap to record huge
   trace log on the disk and to run in background.
   Passing -F option with -o option runs stap in background mode. In this
diff --git a/stap.1.in b/stap.1.in
index 7efa9239..c562c8b7 100644
--- a/stap.1.in
+++ b/stap.1.in
@@ -788,10 +788,12 @@ and dereference the
 .I member
 value.  The optional
 .I module
-tells the translator where to look for information about that type.  If
-the module is not specified, it will default either to the probe module
-for dwarf probes, or to "kernel" for functions and all other probes
-types.
+tells the translator where to look for information about that type.
+Multiple modules may be specified as a list with
+.IR :
+separators.  If the module is not specified, it will default either to
+the probe module for dwarf probes, or to "kernel" for functions and all
+other probes types.
 .PP
 When in guru mode, the translator will also allow scripts to assign new
 values to members of typecasted pointers.