The Structure Of The LDAS Disk Cache File

The LDAS diskcacheAPI records the state of directories containing frame files in a file:

/ldas_outgoing/.frame.cache

This file contains the result of running the Tcl command array get ::disk::cache, which produces a Tcl list consisting of key/value pairs of associative array keys and their stored values.
The structure represented in the file "begins" (the entries are in no particular order, being internally represented as a hash) with the directories defined in the LDASapi.rsc file as the ::MOUNT_PT values. The structure shows descendants of the mount point directories and all frame files found therein.

Each directory has an entry for integrity, which can have the value -1, 0, or 1.

The File (showing the E7 data as on ldas-dev):

/imports/E7 a 'toplevel', an element of ::MOUNT_PT
/imports/E7,integrity -1 no files here
/imports/E7,ifos {} thus no ifos represented
/imports/E7,mtime 1010026050
  
  /imports/E7/LHO 
  a subdir which contains no frames
  /imports/E7/LHO,integrity -1
  /imports/E7/LHO,ifos {}
  /imports/E7/LHO,mtime 1010194183
  /imports/E7/LLO 
  ditto
  /imports/E7/LLO,integrity -1
  /imports/E7/LLO,ifos {}
  /imports/E7/LLO,mtime 1010194188
    
    /imports/E7/LHO/frames
    this is the directory name
    /imports/E7/LHO/frames,integrity 1 
    there are frames here
    /imports/E7/LHO/frames,ifos H 
    for the ifo 'H'
    /imports/E7/LHO/frames,mtime 1010194163
    /imports/E7/LHO/frames,H {} 
    key without value, used for searching 
    /imports/E7/LHO/frames,H,types R 
    only type 'R' frames are found here
      
      /imports/E7/LHO/frames,H,R {} 
      key without value, used for searching
      /imports/E7/LHO/frames,H,R,dts 16 
      only 16 second frames here
      /imports/E7/LHO/frames,H,R,exts gwf 
      all frames here have extension .gwf
      /imports/E7/LHO/frames,H,R,Ns 1 
      all frame files here contain ONE frame object
      /imports/E7/LHO/frames,H,R,1,16,n 450 
      there are 450 frames of this type in this directory
      /imports/E7/LHO/frames,H,R,1,16,name official 
      the frames of this type are named according to the official frame naming convention
      /imports/E7/LHO/frames,H,R,1,16 {693960000 693967200} 
      the frames here cover the contigous time range 693960000-693967200
    
    /imports/E7/LLO/frames
    /imports/E7/LLO/frames,integrity 1
    /imports/E7/LLO/frames,ifos L
    /imports/E7/LLO/frames,mtime 1010194119
    /imports/E7/LLO/frames,L {} 
    key without value, used for searching
    /imports/E7/LLO/frames,L,types R
      
      /imports/E7/LLO/frames,L,R {} 
      key without value, used for searching
      /imports/E7/LLO/frames,L,R,dts 16
      /imports/E7/LLO/frames,L,R,exts gwf
      /imports/E7/LLO/frames,L,R,Ns 1
      /imports/E7/LLO/frames,L,R,1,16,n 450
      /imports/E7/LLO/frames,L,R,1,16,name official
      /imports/E7/LLO/frames,L,R,1,16 {693960000 693967200}
        
    
Note that a directory containing non-contiguous time data will be represented by the time range entry containing as many pairs of begin and end times listed as required to account for all the contained data.

The IFO, type, extension, dt, and N entries MAY consist of lists if the directory contains mixed data.

The value of N is currently always 1. Only the frame API can determine the number of files in a frame file, and it has not yet been decided whether it should participate in the construction of the cache information. There may be a means of determining this value without the use of the frame API; stay tuned.