Work on if, call and system tags.

__system.h

@@ -0,0 +1,26 @@
+#ifndef ____call_h__
+#define ____call_h__
+
+#include "Tag.h"
+
+namespace jet {
+   
+   class __call : public Tag {
+   
+    public:
+      __call(coreutils::ZString &in, coreutils::MString &out, Global &global);
+
+    private:
+      int pid;
+      int status;
+      int ix;
+      int fdi[2];
+      int fdo[2];
+      int rc;
+      char *argv[50];
+      
+   };
+      
+}
+
+#endif