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TrFile_AppendToFile (function reference)

By June 1, 2024June 4th, 2024Online Help, Troi File Plug-in
Troi File Plug-in > Functions reference > TrFile_AppendToFile
Troi File Plug-in for FileMaker Pro


Append characters to the contents of an existing file

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TrFile_AppendToFile ( switches; filepath ; text )


switches these alter the behavior of the function
filepath the path to the file where the text must be appended
text the characters that you want to add at the end of the file


Switches can be empty or one of this:

-Encoding=Native (default)
-Encoding=ISO_8859_1 (Windows Latin-1)
-Encoding=BytesOnly only characters in the range 0-255 are written, others are skipped

This determines the character encoding of the appended data.

You can also add this switch:

-CRtoCRLF Use Windows line endings. Returns in the text parameter are substituted with CRLF (Carriage Return followed by a Line Feed) in the written file.

Returned Result

Data type returned

Error code


The returned result is an error code. An error always starts with 2 dollars, followed by the error code. You should always check for errors. Returned error codes can be:

0 no error The string of characters was added to the file
$$-1 genericErr The file could not be opened for appending (You might need to create the file first).
$$-2 genericErr The file could not be opened for appending (You might need to create the file first).

Other errors may be returned.

Originated in

Troi File Plug-in 9.0


FileMaker Pro 17 to FileMaker Pro 21 (2024)


See also the function:
TrFile_SaveFileDialog to ask the user for a filePath.

Note that the maximum size of text to append with TrFile_AppendToFile is currently 150 million characters (per call to the function). This equals to about max. 600 million characters written. This depends on the encoding, for example one Unicode character encoded as UTF-8 can require up to 4 character in the written file.


Assume your C disk already contains a file “Testtext.txt”, which contains the text “Hello”. We assume that a global number field gErrorCode is defined. Create the following script:

Set Field [ gErrorCode ; TrFile_AppendContentsToFile ( "-Unused" ; C:\Testtext.txt"; " there." ) ]

This script will add the text ” there.” to the end of the file. After running the script once the file will contain “Hello there.”. If you run the script again the file will contain “Hello there. there.”

Example 2

This shows how to write to a log file. We assume that in your FileMaker file the following fields are defined:

gErrorCode		Global, number
gXplatformReturn	Global, text
gLogFilePath		Global, text	  	
gLogtext		Global, text 

gLogFilePath should contain the path to an existing log file, for example “D:\Logs\L2017_01.TXT” (Windows) or “Mac HD:Logs:Log 2017_01” (Mac). gXplatformReturn should contain a return on Mac and a return and a linefeed on Windows. gLogtext is the text you want to log.

Whenever you need to write a line to the log fill the field gLogtext and perform this script step:

Set Field [ gErrorCode ; TrFile_AppendContents (  "-Encoding=UTF8" ; gLogFilePath ;
		DateToText ( Get ( CurrentDate ) ) & " " &
		TimeToText ( Get ( CurrentTime ) ) & " text: " & gLogtext & gXplatformReturn ) ) ]

This script step will add a line every time this script is performed. The log file might look like this:

04/12/2017 10:23:56 text: user Peter logged in
04/12/2017 14:31:02 text: user Peter logged out
04/12/2017 14:31:02 text: closed file “Invoices”

Used in example file


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Append to File

Related topics

Troi File Plug-in online help (overview)

Online Help Page for Troi File Plug-in for 17 to 2024 –> TrFile_AppendToFile (filep4308) 2024-0604 19:42:21