Amanda Amanda@Work.Place Version 3.xx, Installer'S Manual

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82 Installing Amanda@Work.Place
Parameters
Parameters can be required or optional. The syntax places brackets […] around optional
parameters.
Parameters can also be for input or for output. Input parameters provide the information
that Amanda needs in order to perform the action that you requested. For example,
Amanda might need the name of the file in which to store a fax or the telephone number
for a pager. You supply the input parameters and make sure that the information in them is
correct. Input parameters can be literals, variables, or other commands.
Output parameters are parameters that store information you asked Amanda for. Output
parameters are always variables because Amanda must store the information you
requested in a storage location. Usually one command asks for the information, Amanda
stores the information in a variable, and another command uses that variable. For example,
you might use the V() command to retrieve a telephone number from a file. If the output
parameter for the telephone number is %S5, Amanda stores the telephone number in the
variable %S5. Then you use %S5 in a T() command to send a fax using that telephone
number.
The syntax in the guide does not indicate which parameters are input and which are
output. This is clear from the descriptions of the command and parameters.
When a string is used as a parameter, you don’t always need the quotation marks, because
the commas and parentheses serve as delimiters. You must use the quotation marks when a
variable is part (but not all) of the string. For example, if %S0 is MARY and %S5 is HU,
the string "MARY HU" can be used as a parameter with or without quotation marks, but
the strings "%S0 HU", "%S0 %S5", and "%S0 %S5" must have quotation marks. Most
programming languages do not allow you to put variables within strings. The Token
Programming Language allows this, but it only checks for variables within a string if you
delimit that string with quotation marks. You cannot use a number from 0 to 9 after %S1
in a string because Amanda assumes that you meant the variable %S10 or %S11, etc.
Most system variables do not have parameters. However, a couple of system variables
have parameters that affect the contents of that system variable. For example, to use %I,
the system variable that retrieves data from specific fields of specific messages, you use
parameters to indicate which field, message number, and mailbox you want the data from.
Syntax
The exact sequence of characters for each token is defined by its syntax, so you have to
learn to read syntax. The following table shows the conventions used in this guide. They
are similar to the syntax conventions used for other programming languages.
Syntax Convention Meaning
bold Bold is used for characters that must be
used by you exactly as they appear—if
you use them at all.
italics Italics are used for characters that you
must replace with real strings, numbers,
variables, or other commands.