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- File Handlers   
   + Introduction   
   - Lab 1   
      - File Format   
      - Part 1   
      - Part 1 (ctd.)   
      - Part 1 (ctd.)   
      - Part 2   
      - Part 3   
      - Part 4   
      - Solution   
   + Lab 2   
  • Objective:
    • For this lab you will be creating a file handler for a simple file type. At the end of this lab it will be possible to STATUS the new file type and read/write it.
  • File format:
    • The file format we will be supporting will be the ORANGE file format (.orange). ORANGE files hold linearly-sampled data similar to a Type 1000 BLUE file.
    • ORANGE files have a 24 byte header followed by the data. All data in the file is either ScalarLong (SL) or SclarFloat (SF).
    • The file header contained the following fields:
      Byte OffsetType Name Default Value Description
      0 char[6]Version"ORANGE" File version always "ORANGE".
      7 char[2]Format "SL" Data format ("SL" or "SF").
      8 double XStart 0.0 X-axis start value.
      16 double XDelta 1.0 X-axis delta value.
      Note that char[6] and char[2] reference Strings of length 6 and 2 respectively.
    • The data portion immediately follows the header (i.e. starting at byte offset 24). The data portion extends to the end of the file (unlike a BLUE file there is no "extended header" at the end of the file).
    • All information in the header, and all of the data is stored using little-endian byte order (EEEI). (For those unfamilar with byte ordering, think of it as defining whether you write left-to-right or right-to-left.)
  • continued on next page
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