# HG changeset patch
# User Rik <rik@octave.org>
# Date 1390583388 28800
# Node ID d1e16bdb39581a5510df7bc4d2cf8043a2a8d42b
# Parent  2e62b1f01bfece6a5c10ba60006f22085a34abc1
myfeval.c: Fix segfault in mex example code.

* myfeval.c: Correctly cast away const attribute of prhs[].
Also, add code to work with Octave's built-in 'ans' variable.

* external.txi: Update example in External Code Interface for myfeval.

diff -r 2e62b1f01bfe -r d1e16bdb3958 doc/interpreter/external.txi
--- a/doc/interpreter/external.txi	Fri Jan 24 04:19:00 2014 -0500
+++ b/doc/interpreter/external.txi	Fri Jan 24 09:09:48 2014 -0800
@@ -1712,12 +1712,11 @@
 
 @example
 @group
-myfeval ("sin", 1)
 a = myfeval ("sin", 1)
-@result{} Hello, World!
-    I have 2 inputs and 1 outputs
-    I'm going to call the interpreter function sin
-    a =  0.84147
+@result{} Starting file myfeval.mex
+   I have 2 inputs and 1 outputs
+   I'm going to call the interpreter function sin
+   a =  0.84147
 @end group
 @end example
 
@@ -1811,8 +1810,7 @@
 
 This is the norm of the matrix:
 34.4952
-
+$
 @end group
 @end example
 
-
diff -r 2e62b1f01bfe -r d1e16bdb3958 examples/myfeval.c
--- a/examples/myfeval.c	Fri Jan 24 04:19:00 2014 -0500
+++ b/examples/myfeval.c	Fri Jan 24 09:09:48 2014 -0800
@@ -6,7 +6,7 @@
 {
   char *str;
 
-  mexPrintf ("Hello, World!\n");
+  mexPrintf ("Starting file myfeval.mex\n");
 
   mexPrintf ("I have %d inputs and %d outputs\n", nrhs, nlhs);
 
@@ -17,7 +17,11 @@
 
   mexPrintf ("I'm going to call the function %s\n", str);
 
-  mexCallMATLAB (nlhs, plhs, nrhs-1, (mxArray*)prhs+1, str);
+  if (nlhs == 0)
+    nlhs = 1;  // Octave's automatic 'ans' variable
+
+  /* Cast prhs just to get rid of 'const' qualifier and stop compile warning */
+  mexCallMATLAB (nlhs, plhs, nrhs-1, (mxArray**)prhs+1, str);
 
   mxFree (str);
 }