What's New Since Version 2.0?

The following items are new in version 2.1:

• Various code optimizations with respect to the lousy performance of version 2.0 have been performed.
• ddu_set_dd_wait has been introduced. The wait mode while retrieving events is now a property of the process and not the fifo. In particular two processes with different wait modes can read from the same fifo. In addition one can change the wait mode at any time.
• A bug in the fifo monitor programs has been fixed.
• The directory structure has been changed, such that $DD_BIN and $DD_LIB has specific subdirectories depending on the UNIX platform.

The following items are new in version 2.2a:

• dds_flush added
• ddu_creq_fev added for conditional event request
• ddu_get_free_buffers() added. Returns the number of free buffers in the system.

The following items are new in version 2.3:

• The network part has been completely rewritten
• dd_log replaces any printf statements to stdout or stderr
• dd_cleanup: an example script on how to really cleanup leftover processes

The following items are new in version 2.5:

• dds_flush() : fixed bug discovered by M.Leitch
• dd_link() : fixed bug in transfer of fifoname.
• ddu_fifo_exist(char *fifoname: finds out whether a fifo named fifoname exists
• ddu_init(char *fifoname struct fifo_mode fmode) : changed calling sequence to allow to have a fifo with one and only one process attached to it. Replaced the many calling arguments with the following C structure:

   
  		  struct fifo_mode {
  
  		 		  int mode;
  
  		 		  int wait;
  
  		 		  int prescale;
  
  		 		  int suser;
  
  		 		  int *p2ctl;
  
  		 };
  
  

  The members of the structures are the same as the old calling arguments of ddu_init. fifo_mode.suser is a flag to indicate that the fifo is in single user mode (i.e. only one process can be attached to it). The valid values of fifo_mode.suser are FMODE_SINGLE_USER or FMODE_MULTI_USER. The default value is FMODE_MULTI_USER.

• ddu_set_brccmd:
  Upon a broadcast there is the option to call a function depending on the value of fev.ctlb2. ddu_set_brccmd sets the pointer to that function.
• dds_flush(int brc_flag) :
  Added argument brc_flag to determine whether a broadcast should be made at the end of dds_flush . This is used in dd_link to propagate the flush over the network.
• Created $DD_USR directory as a placeholder in case header files and source code are changed by the user.
• Changed from Tcl7.3 and Tk3.6 to Tcl7.4 and Tk4.0
• Ported to the Alpha (bin/lib subdirectory OSF1).
• Extended dd_link to support block transfer.