IMS type-1 command format

Subsections:

• Command recognition character
• Verb
• Keywords
• Parameters
• Null keywords
• Comments
• Passwords

Command recognition character

The slash (⁄) is the command recognition character for IMS commands. In a DBCTL environment, another character can be defined as the command recognition character and would replace the slash.

Verb

The /VERB (such as /STOP) is the first command element and identifies the action to be taken. To abbreviate a verb, use only the slash and the first three characters. Enter the characters using either uppercase or lowercase letters.

Keywords

IMS keywords are reserved words identifying IMS resources that relate to transaction management, databases, or the IMS system. Many commands require one or more keywords.

Table 1 is a list of available keywords and their synonyms. The alphabetic list of keywords after Table 1 explains the use of the keyword for each IMS command it affects.

Keywords are shown in uppercase. The keyword or an allowable synonym can be entered in uppercase or lowercase.

Parameters

Parameters refer to installation defined or created resources, such as nodes, databases, or physical terminals, or IMS reserved parameters. Parameters in IMS commands must be replaced with parameter values. Reserved parameters have a unique meaning to IMS and refer to system resources or functions.

The format of the parameters that can be entered is determined by the command and keyword with which they are associated. Use the syntax example provided at the beginning of each command description to determine the valid parameter formats for that command.

When commands are entered, parameters are separated from a keyword by a space or an equal sign (=). Multiple parameters are separated by a comma, a blank, or a comma followed by a blank. The last parameter of one keyword is separated from the next keyword either by a space, a comma, or an equal sign.

In the syntax examples, default parameters appear above the syntax line. Optional parameters appear below the syntax line.

   .-----------.   
   V           |   
>>---parameter-+-----------------------------------------------><

Reserved words

The resources you define, such as nodes, physical terminals, and databases, may be referenced as parameter values in IMS commands. Do not use reserved words to name these resources, or IMS might not interpret the command as expected. For example, if you define a node called TKOTRA and issue a /DISPLAY NODE TKOTRA command, IMS will list all the nodes that have an attribute of TKOTRA, instead of the specific node named TKOTRA.

ALL parameter

Entering the reserved parameter ALL specifies all defined resources related to that keyword. ALL cannot be used with every command.

ALL=NO or ALL=DIS can be specified on the KEYWD macro to prevent use of the ALL parameter. ALL=NO and ALL=DIS can be specified for all keywords. ALL=NO indicates that the ALL parameter is invalid on all the commands for the keyword. ALL=DIS indicates that the ALL parameter is invalid on all the /DISPLAY commands for the keyword.

Inclusive parameters

To use inclusive parameters, enter the first parameter, a hyphen, then the last parameter (parameter1-parameter2).

For the LINE, PTERM, and LINK keywords, the group of parameters specified is assumed to be based on numeric sequence; that is, entering 3-6 specifies parameters 3, 4, 5, and 6. Inclusive parameters are limited to the PTERM keyword when it appears with the LINE keyword in a command. For the NODE keyword, the group of parameters must be static and based on the IMS definition sequence, not numeric or alphabetic sequence.

Generic parameters

You can use generic parameters to specify a group of resources whose names match a 1- to 8-character alphanumeric mask. Generic parameters apply to both type-1 and type-2 commands.

A generic parameter can include one or more of the following wildcard characters:

*

Matches zero or more characters. When used alone, it matches all the names for the keyword or resource.

%

Matches exactly one character.

The following examples illustrate some uses of wildcard characters:

CO*

Matches any string of any length that begins with CO. For instance: CO, COO, COOP

%%S

Matches any 3-character string that ends with S. For instance: IMS, XYS

CO*%%1

Matches any string of 5 or more characters that starts with CO, ends with 1, and has at least 2 characters between CO and 1. For instance: CONV1, CONV21, CONV221, CONV23B1

Specifying an asterisk alone as the generic parameter (such as NAME(*)) is equivalent to specifying ALL (such as NAME(ALL)). However, depending on the installation, other generic parameters can mean ALL. For example, the generic parameter %%%% means ALL to an installation whose resource names are all 4 characters long. Some commands support NAME(*) and do not support NAME(ALL) for a wildcard name.

When a generic parameter is used, IMS uses a serial search of all resources to match the generic name. Using a serial search of all resources can have performance implications in larger systems.

The following table lists some of the type-1 commands and keywords that support generic parameters.

Group parameters

A group parameter allows easy specification of a group of resources, where the resources in the group are defined and managed by the installation. Group parameters apply to both type-1 and type-2 command.

Group parameters are supported with the DATAGRP keyword for the /DBRECOVERY, /START, /STOP, and UPDATE (type-2) commands. A group name is one to eight characters long. It is associated with a list of databases, DEDB areas, or database data sets.

A database group name and its associated databases or DEDB areas is defined in the DBRC RECON data set using the DBRC INIT.DBDSGRP command with parameters GRPNAME and DBGRP.

Groups defined for commands should contain only databases and areas for use with the DATAGROUP keyword.

Null keywords

Comments

You can add comments or notes to the end of a command. When you add comments, identify the end of the command by entering a period after the last parameter. If you do not enter a period, residual data from a 3270 affects command processing.

Passwords

Depending on the password security arrangement of the defined IMS system and the terminal where the command is entered, a password can be required after the command verb, or after a parameter or a keyword of certain commands.

If a command password is required, it must be entered immediately after /VERB and is normally enclosed in parentheses. No spaces or intervening characters are allowed between the /VERB and the left parenthesis.

When using MFS, if a command password is required, the installation-defined MFS format must contain a defined password field. The password must be entered into the password field defined by the format displayed. If command entry field of the format is defined to accept the command verb only, message DFS1051 is issued when an attempt is made to enter /VERB(password).

None of the IMS-supplied default formats (exception for the master terminal format) have a password field defined.

You must use RACF® or an equivalent security product to require a command verb password associated with the user ID signed on to the dynamic terminal.

The /LOCK and /UNLOCK command keywords and parameters support passwords.

The /LOCK and /UNLOCK command parameters also support passwords when defined for users using RACF for static and dynamic resources. The password associated with a signed on user and specified after a command resource parameter will be used to perform a reverification check, if the resource is defined to RACF with 'REVERIFY' specified in the APPLDATA field. If the resource passes the RACF authorization check, and RVFY=Y is specified as an IMS startup parameter, IMS will verify that the password following the parameter is the same as the password entered during signon for the user that entered the command. If 'REVERIFY' is specified for a resource, but a password is not provided, or the wrong password is provided, the command processing for that resource will be rejected. This is also true for the /SET TRANSACTION and /SET CONVERSATION commands.

The use of passwords is not shown in the examples.