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This section describes how to read the syntax diagrams that are used in this manual. To read a syntax diagram, follow the path of the line. Read from left to right, and top to bottom.
Syntax items, such as a keyword or a variable, can be:
Table 1. Description of Syntax Diagram Items
Syntax Diagram Description | Example |
---|---|
Abbreviations:
Uppercase letters indicate the shortest acceptable form. If an item appears entirely in uppercase letters, you cannot shorten it. Type the item in any combination of uppercase or lowercase letters. In this example, you can enter any of these choices either in uppercase or lowercase letters: KEYWO, KEYWORD, or KEYWOrd. |
>>-KEYWOrd----------------------------------------------------->< |
Symbols:
Enter these symbols exactly as they appear in the syntax diagram. |
|
Variables:
Italicized lowercase items (var_name) indicate variables. In this example, you can specify a var_name when you enter the KEYWOrd command. |
>>-KEYWOrd--var_name------------------------------------------->< |
Repetition:
An arrow returning to the left indicates that you can repeat the item. A character or space within the arrow indicates that you must separate repeated items with a character or space. A footnote indicates the number of times that you can repeat the item. |
.--------. V | >>---repeat-+--------------------------------------------------><
.-,------. V | >>---repeat-+-------------------------------------------------->< .-------------. V (1) | >>---repeat------+---------------------------------------------><
Notes:
|
Required Choices:
When two or more items are in a stack and one of them is on the line, you must select one item. In this example, you must select either A, B, or C. |
>>-+-A-+------------------------------------------------------->< +-B-+ '-C-' |
Optional Choice:
When an item is below the line, that item is optional. In the first example, you can select either A or nothing at all. When two or more items are in a stack below the line, all of them are optional. In the second example, you can select A, B, C, or nothing at all. |
>>-+---+------------------------------------------------------->< '-A-' >>-+---+------------------------------------------------------->< +-A-+ +-B-+ '-C-' |
Defaults:
Defaults are above the line. The default is selected unless you override it, or you can select the default explicitly. To override the default, include an option from the stack below the line. In this example, A is the default. Select either B or C to override A. |
.-A-. >>-+---+------------------------------------------------------->< +-B-+ '-C-' |
Repeatable Choices:
A stack of items followed by an arrow returning to the left indicates that you can select more than one item, or in some cases, repeat a single item. In this example, you can select any combination of A, B, or C. |
.-------. V | >>---+-A-+-+--------------------------------------------------->< +-B-+ '-C-' |
Syntax Fragments:
Some diagrams, because of their length, must fragment the syntax. The fragment name displays between vertical bars in the diagram. The expanded fragment displays between vertical bars in the diagram after a heading with the same fragment name. |
>>-| The fragment name |--------------------------------------->< The fragment name .-A-. |--+---+--------------------------------------------------------| +-B-+ '-C-' |