Start a task, passing it a channel.
START CHANNEL >>-START--TRANSID(name)--CHANNEL(name)--------------------------> >--+--------------------+--+-------------------+--------------->< +-TERMID(name)-------+ '-SYSID(systemname)-' '-USERID(data-value)-'
Conditions: CHANNELERR,
INVREQ, ISCINVREQ,
NOTAUTH, RESUNAVAIL, SYSIDERR, TERMIDERR, TRANSIDERR, USERIDERR
START CHANNEL starts a task, on a local or remote system, passing it a channel.
Typically, the starting task uses the channel to pass data to the started task (although in some circumstances the channel may be empty—see the description of the CHANNEL option). The starting task may also specify a terminal to be used by the started task as its principal facility.
Each START CHANNEL command results in a separate task being started.
Some transactions started by a subset of START commands can be dynamically routed to a remote region. For general information about dynamic transaction routing, and specific information about which transactions started by START commands are eligible for dynamic routing, see the CICS® Intercommunication Guide.
These exposures result from the delay between the execution of the START and the time of task creation. Even on a START CHANNEL request, when the START is always immediate, CICS may delay creating the task, either because the required terminal is not free or because of other system constraints.
You can use INQUIRE commands to ensure that the transaction and program are enabled at the time of the START command, but either may become disabled before task creation.
Channel names are always
in EBCDIC. The allowable set of characters for channel names, listed above,
includes some characters that do not have the same representation in all EBCDIC
code pages. We therefore recommend that, if channels are to be shipped between
regions, the characters used in naming them should be restricted to A-Z a-z
0-9 & : = , ; < > . - and _.
The started task is given a copy of the channel's containers (and the data they contain). The copy is made when the START command is issued.
The terminal identifier must be defined as either a local or a remote terminal on the system in which the START command is executed.
If SYSID is specified, and names a remote system, the transaction is assumed to be on that system irrespective of whether or not the transaction definition is defined as remote in the PCT. Otherwise the transaction definition is used to find out whether the transaction is on a local or a remote system.
If you omit both TERMID and USERID, CICS uses instead the userid under which the transaction that issues the START command is running. This is referred to as userid2.
By using either userid1 or userid2 CICS ensures that a started transaction always runs under a valid userid, which must be authorized to all the resources referenced by the started transaction.
CICS performs a surrogate security check against userid2 to verify that this user is authorized to userid1. If userid2 is not authorized, CICS returns a NOTAUTH condition. The surrogate check is not done here if USERID is omitted.
Also occurs (RESP2 not set) if the START command is not valid for processing by CICS.
Default action: terminate the task abnormally.
Default action: terminate the task abnormally.
The security access capabilities of the transaction that issued the command do not allow the command to be performed with the value specified in the USERID option. The security access capabilities of the transaction have been established by the external security manager according to user security, and whether link security or the execution diagnostic facility (EDF) have been in use.
Default action: terminate the task abnormally.
RESUNAVAIL is returned on the EXEC CICS START command executed by the mirror in the target region, if an XICERES global user exit program indicates that a required resource is unavailable on the target region. It is not returned to the application.
Default action: reinvoke the distributed routing program for route selection failure.
In all the above cases, the nature of the error is indicated by the second byte of the EIBRCODE.
Default action: terminate the task abnormally.
The SYSIDERR condition may not be raised if the user exit XISLCLQ is enabled (see the CICS Customization Guide for programming information).
Default action: terminate the task abnormally.
Default action: terminate the task abnormally.
Default action: terminate the task abnormally.