Mhist

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Description

The mhist utility dumps data from the History system. You specify which events/tags you're interested in and the time period to query, and the results will be printed to screen.

Arguments

If no arguments are provided, an interactive session will be started that will prompt the user to answer questions about which data should be dumped. The questions are the equivalent of the -e, -v, -h and -t arguments (i.e. show data for the most recent N hours for a single event/variable).

[-e Event Name] 
[-v Variable Name]
[-i Index] index of variables which are arrays
[-i Index1:Index2] index range of variables which are arrays (max 50)
[-t Interval] minimum interval in sec. between two displayed records
[-h Hours] display between some hours ago and now
[-d Days] display between some days ago and now
[-f File] specify history file explicitly
[-s Start date] specify start date YYMMDD[.HHMM[SS]]
[-p End date] specify end date YYMMDD[.HHMM[SS]]
[-l] list available events and variables
[-b] display time stamp in decimal format

Examples

To enter an interactive session: 
  mhist

To list all existing events and variables: 
  mhist -l

To show data for all variables in event "ExampleEvent" for the last 10 days, with at most one datapoint per minute: 
  mhist -e ExampleEvent -d 10 -t 60

Same as before, but show timestamps as integers (UNIX timestamps) rather than strings like "Mar 30 14:16:14": 
  mhist -e ExampleEvent -d 10 -t 60 -b

Notes

The mhist source code can be found in the Midas package under ../midas/progs.