Fix CAS input on windows (bug 10262)

This is the well known file locking problem: The TempFile class keeps the
created file locked for the own process, and this prevents the CAS to read it.

src/mathed/MathExtern.cpp

@@ -1000,8 +1000,13 @@ namespace {
 	{
 		// In order to avoid parsing problems with command interpreters
 		// we pass input data through a file
-		TempFile tempfile("casinput");
-		FileName const cas_tmpfile = tempfile.name();
+		// Since the CAS is supposed to read the temp file we need
+		// to unlock it on windows (bug 10262).
+		auto_ptr<TempFile> tempfile(new TempFile("casinput"));
+		tempfile->setAutoRemove(false);
+		FileName const cas_tmpfile = tempfile->name();
+		tempfile.reset();
+
 		if (cas_tmpfile.empty()) {
 			lyxerr << "Warning: cannot create temporary file."
 			       << endl;
@@ -1015,6 +1020,7 @@ namespace {
 		lyxerr << "calling: " << cmd
 		       << "\ninput: '" << data << "'" << endl;
 		cmd_ret const ret = runCommand(command);
+		cas_tmpfile.removeFile();
 		return ret.second;
 	}
 

status.22x

@@ -81,6 +81,8 @@ What's new
 
 - Load math packages automatically with JSS template (bug 9242).
 
+- Calling a Computer Algebra System from LyX works again (windows only bug 10262).
+
 
 * LYX2LYX