This video gives basic information on Using the FILETRUNC "Truncate File" instruction in the Do-more Designer software. It presents information that is commonly missed by users. This WILL NOT be a complete tutorial for the instruction but rather a supplement to the help file and customer experience.
This instruction will delete the contents of the specified file, from the location of the File pointer, to the end of the file. The location of the File pointer, in a currently opened file, is stored in the. FILEPOINTER field of the of the File handle structure. A typical use for this instruction, would to be first, open the file, using the FILEOPEN instruction. Use the File seek to point to the location where the truncation is to happen, and then use this instruction. Now, this instruction can be used in Task or Program but cannot be used in Subroutines or Interrupt service routines.