SYS(2007) Algorithm for Checksum

Last reviewed: June 27, 1995
Article ID: Q101289
The information in this article applies to:
  • Microsoft FoxPro for Windows, versions 2.5, 2.5a, and 2.5b
  • Microsoft FoxPro for MS-DOS, versions 2.0, 2.5, 2.5a, and 2.5b
  • Microsoft FoxPro for Macintosh, version 2.5b

The SYS(2007) function returns the checksum value of the character expression <expC>. The correct syntax is SYS(2007,<expC>). A checksum can be used to test the validity of data or to compare two character expressions.

NOTE: Checksum is a "byte-oriented CRC-16" algorithm. The exact logic was last published in the February 1986 edition of "Dr. Dobbs Journal."


Additional reference words: FoxMac FoxDos FoxWin 2.00 2.50 2.50a 2.50b
check sum
KBCategory: kbprg
KBSubcategory: FxprgGeneral


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Last reviewed: June 27, 1995
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