//------------ prototypes --------------------------------------------------------------
extern void mcl_fifo_fanout( void* ctx, int report, int long_hdrs );
-extern int mcl_fifo_one( void* ctx, char* payload, int plen, int mtype );
+extern int mcl_fifo_one( void* ctx, const char* payload, int plen, int mtype );
extern rmr_mbuf_t* mcl_get_msg( void* vctx, rmr_mbuf_t* msg, int timeout );
-extern void* mcl_mk_context( char* dir );
+extern void* mcl_mk_context( const char* dir );
extern int mcl_fifo_read1( void* vctx, int mtype, char* ubuf, int ublen, int long_hdr );
extern int mcl_fifo_tsread1( void* vctx, int mtype, char* ubuf, int ublen, int long_hdr, char* timestamp );
extern int mcl_set_sigh( );