TRUNC Function (File)
Truncate an ASCII or binary file to the current position of the file pointer.
Syntax
File.TRUNC
Parameters
File
Type: File
Use this variable to refer to the file.
Remarks
Typically, you use this function together with SEEK Function (File). Use File.SEEK to position the pointer in the file and then use File.TRUNC to truncate the file at that point.
Example
The following example sets a pointer at position 20 in a file and truncates the file at the pointer position. The WRITEMODE Function (File) allows the file that is named C:\TestFolder\TestFile.txt to open in write mode. The SEEK function sets a pointer at position 20 in the file and then the TRUNC Function (FILE) truncates the contents at the pointer position. This example assumes that you have created a text file named C:\TestFolder\TestFile.txt. The file is then saved a truncated file. This example requires that you create the following variable in the C/AL Globals window.
| Variable name | DataType |
|---|---|
| TestFile | File |
TestFile.WRITEMODE(TRUE);
TestFile.OPEN('C:\TestFolder\TestFile.txt');
TestFile.SEEK(20);
TestFile.TRUNC;