Section 3(cbl) - COBOL Functions

ATMI COBOL Function Reference

TPBROADCAST(3cbl)

Name

TPBROADCAST() - broadcast notification by name

Synopsis

01 TPBCTDEF-REC.
  COPY TPBCTDEF. 
 
01 TPTYPE-REC.
  COPY TPTYPE. 
 
01 DATA-REC.
  COPY User data. 
 
01 TPSTATUS-REC.
  COPY TPSTATUS. 
 
CALL "TPBROADCAST" USING TPBCTDEF-REC TPTYPE-REC DATA-REC TPSTATUS-REC.

Description

TPBROADCAST() allows a client or server to send unsolicited messages to registered clients within the system. The target client set consists of those clients matching identifiers passed to TPBROADCAST(). Wildcards can be used in specifying identifiers.

LMID, USRNAME and CLTNAME, all in TPBCTDEF-REC, are logical identifiers used to select the target client set. A SPACES value for any logical identifiers constitutes a wildcard for that argument. A wildcard argument matches all client identifiers for that field. Each identifier must meet the size restrictions defined for the system to be considered valid, that is, each identifier must be between 0 and 30 characters in length.

The data portion of the request is identified by DATA-REC and LEN in TPTYPE-REC specifies how much of DATA-REC to send. Note that if DATA-REC is a record of a type that does not require a length to be specified, then LEN is ignored (and may be 0). If REC-TYPE in TPTYPE-REC is SPACES, in which case DATA-REC and LEN are ignored and a request is sent with no data portion.

The following is a list of valid settings in TPBCTDEF-REC.

TPNOBLOCK

The request is not sent if a blocking condition exists (for example, the internal buffers into which the message is transferred are full). Either TPNOBLOCK or TPBLOCK must be set.

TPBLOCK

If a blocking condition exists, the caller blocks until the condition subsides or a timeout occurs (either transaction or blocking timeout). Either TPNOBLOCK or TPBLOCK must be set.

TPNOTIME

This setting signifies that the caller is willing to block indefinitely and wants to be immune to blocking timeouts. Transaction timeouts may still occur. Either TPNOTIME or TPTIME must be set.

TPTIME

This setting signifies that the caller will receive blocking timeouts if a blocking condition exists and the blocking time is reached. Either TPNOTIME or TPTIME must be set.

TPSIGRSTRT

If a signal interrupts any underlying system calls, then the interrupted system call is reissued. Upon successful return from TPBROADCAST(), the message has been delivered to the system for forwarding to the selected clients. TPBROADCAST() does not wait for the message to be delivered to each selected client. Either TPNOSIGRSTRTor TPSIGRSTRT must be set.

TPNOSIGRSTRT

If a signal interrupts any underlying system calls, then the interrupted system call is not restarted and the call fails. Either TPNOSIGRSTRT or TPSIGRSTRT must be set.

Return Values

Upon successful completion, TPBROADCAST() sets TP-STATUS to [TPOK].

Errors

Under the following conditions, TPBROADCAST() sends no broadcast messages to application clients and sets TP-STATUS to:

[TPEINVAL]

Invalid arguments were given. Note that use of an illegal LMID will cause TPBROADCAST() to fail and return TPEINVAL(). However, non-existent user or client names will simply successfully broadcast to no one.

[TPETIME]

A blocking timeout occurred. (A blocking timeout can occur only if both TPBLOCK and TPTIME are specified.)

[TPEBLOCK]

A blocking condition was found on the call and TPNOBLOCK was specified.

[TPGOTSIG]

A signal was received and TPSIGRSTRT was not specified.

[TPEPROTO]

TPBROADCAST() was called improperly.

[TPESYSTEM]

A BEA Tuxedo system error has occurred. The exact nature of the error is written to a log file.

[TPEOS]

An operating system error has occurred.

Portability

The interfaces described in TPNOTIFY() are supported on native site UNIX-based processors. In addition, the routines TPBROADCAST() and TPCHKUNSOL() as well as the routine TPSETUNSOL() are supported on UNIX and MS-DOS workstation processors.

Usage

Clients that select signal-based notification may not be signal-able by the system due to signal restrictions. When this occurs, the system generates a log message that it is switching notification for the selected client to dip-in and the client is notified then and thereafter via dip-in notification. (See UBBCONFIG(5) description of the RESOURCES NOTIFY parameter for a detailed discussion of notification methods.)

Because signaling of clients is always done by the system, the behavior of notification is always consistent, regardless of where the originating notification call is made. Therefore to use signal-based notification:

A native client must be running as an application administrator.
A Workstation client is not required to be running as the application administrator.

The ID for the application administrator is identified in the configuration file for the application.

If signal-based notification is selected for a client, then certain ATMI calls can fail, returning TPGOTSIG() due to receipt of an unsolicited message if TPSIGRSTRT is not specified. See UBBCONFIG(5) and TPINITIALIZE(3cbl) for more information on notification method selection.