8.5.9 GetTextPosition (return the current read/write position)

Purpose

Returns the current read/write position in a text file.

Syntax

GetTextPosition (FileId)

Argument

FileId

Specify the file ID as a number or as a variable that stores this value.

This file ID is the execution result returned by the TextOpen command.

Description

The GetTextPosition command acquires the current read/write position in the text file specified by the file ID, as the number of bytes from the beginning of the file (0). The command returns the current read/write position on successful execution, or a zero-length string ("") if an error occurs.

An error results if the read/write start position is beyond 2,147,483,647.

Example

' Change the string "Start" in the text file "Loging.txt"
' in the execution folder to "Start script execution".
Dim  file1
file1 = TextOpen ( _BIN_+"Loging.txt" ,ReadWrite )
If  file1 = 0  Then
  MessageBox ( _BIN_+"Failed to open Loging.txt" ,OK )
Else
  Dim  line ,position ,buff
  For  line = 1 To 10
    ' Acquire the read/write position.
    position = GetTextPosition ( file1 )
    If  TextRead ( file1 ,buff )  Then
      If  buff = "Start"  Then
        ' Overwrite the text at the read/write position.
        TextWrite ( file1 ,"Start script execution" ,True ,position )
      End
    Else
      Exit For
    End
  Next
  TextClose (file1)
End

JP1/Script version

Supported from JP1/Script 05-00.

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