Administration > Developing Error Messages for Custom Applications > Creating Error Messages for Custom ACL Applications > Format of the .xlf files
  
Format of the .xlf files
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The format of the .xlf files is described briefly below. When you create .xlf files for your application, you must adhere to this format. Refer to the OASIS XLIFF 1.1 Specification available at www.oasis-open.org/committees/xliff/documents/cs-xliff-core-1.1-20031031.htm for complete information on the format.
Each message or string in the .xlf file contains one trans-unit element with source and target child elements as follows:
• trans-unit — The parent element for the message. The id attribute specifies a unique message identifier for the string. The restype attribute is set to string if the message is a user interface element or message fragment, or message if it is an error message. The message id is displayed as part of the message in the latter case.
• source — The identifying string for this message.
• target — The actual text of the message or string that appears in Arbortext Editor.
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If you are translating messages into another language, the target string may contain Unicode characters since the XLIFF format is UTF-8 encoded XML. However, the source element is stored in the compiled message file as 8-bit characters. The source element must remain in the 8-bit character set.