Mevb

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mevb - event builder utility

mevb is an event builder application which takes the MIDAS data output from several frontends, and assembles them into a new overall MIDAS event.

Two types of event builder can be envisaged:

  • Asynchronized data collection
  • Synchronized data collection

In the case where overall data collection is handled by multiple physically separated frontends, it could be necessary to assemble these data fragments into a dedicated event. The synchonization of the fragment collection is left to the user, which is done usually through a specific hardware mechanism.

Once the fragments are composed in each frontend, they are sent to the Event Builder (eb) where the serial number (pheader-\>serial_number) of each fragment is compared one event at a time for serial match. In case of a match, a new event will be composed with its own event ID and serial number, followed by all the expected event fragments. The composed event is then sent to the next stage which is usually the data logger mlogger.

mhttpd will present the status of the event builder as an extra equipment with its corresponding statistical information.

Arguments

  [-h ] : help
  [-h hostname ] : host name 
  [-e exptname ] : experiment name
  [-i index ]  : equipment index identification
  [-b buffer_name ] : Buffer name
  [-v ] : Show wheel
  [-d ] : debug messages
  [-D ] : start program as a daemon

Usage

 Thu> mevb -e midas
 Program mevb/EBuilder version 2 started


See also Event Builder.