Campbell Scientific RTDAQ Software - Manual (Page 294)

Section 10. Utilities
Specific
By selecting the Specific option and entering a number, Split will "seek"
that position in the file. This option saves time by starting (or stopping)
part way through a large data file. The number specifies the number of
bytes into the file to seek before processing data. A positive or negative
number can be entered. If the number is positive, Split will start reading
from the beginning of a file; if the number is negative, Split will start
reading from the end of a file. All characters, including spaces, carriage
returns, and line feeds, are counted.
In the following figure, Split will skip the first 256 bytes of data before it
begins processing the data in Input File.
Align Array
When using a specific start offset, the number of bytes specified may
cause Split to seek to the middle of a row. Selecting the Align Array
check box will cause Split to begin processing at the beginning of the next
row.
Stop Offset
This number specifies the number of bytes from the beginning of the file
that Split should stop processing the data file.
In the following figure, Split will skip the first 256 bytes of data before
beginning and stop execution on byte 1024.
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