CCSID support for messages

Use CCSID support for handling messages and message catalogs on i5/OS™.

You can send messages tagged with one CCSID to users with a different CCSID. You can use CCSID support to handle messages by using commands and application programming interfaces.

For example, if you do not set CCSID support on, the following message, encoded in CCSID 00037:

  Joe, I need to see you right away!

appears to a user with CCSID 00500 as

  Joe, I need to see you right away]

Instead of seeing an exclamation mark (!), Joe sees a right square bracket (]). If you set CCSID support on, the text in a message encoded in CCSID 00037 is converted to CCSID 00500. Both the person sending the message and the person receiving the message see identical text.

CCSID support helps preserve data integrity in messages. As you read through this information, you will see other advantages to using CCSID support for messages.

Object-level CCSIDs

• Message files
  • Message-level support
  • Message description-level support
• Message queues
• Job message queues
• System reply lists
• History log

The following topics provide detailed information about message support:

• Setting up CCSID support for message handling
• CCSID support for message catalogs
• Converted character replacement data type field
• Retrieve messages
• Receive messages
• Common questions about CCSID support for message handling

• Handle messages with a specific object-level CCSID
  The objects listed in this topic support CCSIDs. Each of them has an object-level CCSID.
• Message-level support
  When a message is sent to a message queue, you must communicate the CCSID of the replacement data or the immediate message text to the operating system. Use the CCSID parameter on any of the send message commands or APIs to communicate this CCSID to the operating system.
• Message description-level support
  When a message description is added to a message file, the CCSID of the message text must be communicated to the operating system. These topics also discuss how the CCSID of a message description is set and how to change the CCSID of a message description.
• Message queues
  If you set CCSID processing on, system-supplied display files and printer files that display or print messages convert the CCSID of the message queue to the CCSID of the job before displaying or printing the messages.
• Job message queues
  The CCSID for all job message queues is 65534. You cannot change or display this value. A job message queue CCSID of 65534 requires fewer CCSID conversions. Fewer CCSID conversions of text result in better performance and improved data integrity.
• System reply list
  The system reply list has a CCSID of 65534. You cannot change or display this value.
• History log
  The history log is a database file that is tagged with CCSID 65535. You cannot change the CCSID of the history log. No conversions occur when you do database retrievals from the history file.
• Set up CCSID support for message handling
  The default setting of the CCSID for creating message queues and message files is 65535. Most message files delivered with the operating system have a CCSID of 65535.
• CCSID support for message catalogs
  The Message catalog CCSID (CLGCCSID) parameter allows you to specify the CCSID for storing data in a message catalog.
• Converted character replacement data type field
  A replacement data type field supports CCSID processing. This replacement data type field is called a convertible character field (*CCHAR). A *CCHAR replacement data type field is a variable-length field. This field may increase or decrease in length when the field is converted.
• Retrieve messages
  The Retrieve Message (RTVMSG) command and retrieve message (QMHRTVM) application programming interface (API) have a CCSID-to-convert-to parameter. This parameter determines which CCSID the first- and second-level text is converted to before the text is returned to the user.
• Receive messages
  The Receive Message (RCVMSG) command, the Receive Nonprogram Message (QMHRCVM) API, and the Receive Program Message (QMHRCVPM) API have a CCSID-to-convert-to parameter. This parameter determines which CCSID the text or data is converted to before it is returned to the user.
• Common questions about CCSID support for handling messages
  Here are some common questions asked about CCSID support for handling messages.