HP 64783A, User Manual

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Parameters must be declared at the beginning of a command file using the PARMS
keyword. Parameters are preceded by an ampersand (&) and consist of a
combination of one or more letters or underscores. Letters may be upper-case or
lower-case.
Using &ArG_lEfT in Command Files
A command file may contain a special argument named &ArG_lEfT. This special
argument does not have to be declared using the PARMS keyword. It can be used
in command files containing other parameters, or in command files that do not
contain any parameters. This special argument can accept the union of zero or more
command line arguments as a single argument. See “To increase flexibility of
command files by using &ArG_lEfT” for more information.
Using UNIX Commands and Scripts with Command Files
Command files may include UNIX commands and may call shell scripts. Some
commands are recognized directly by the interface (pwd, for example) while others
require a preceding exclamation point (!) to identify them as shell commands.
Using Shell Variables with Command Files
Command files may contain shell variables. Command files only support shell
variables beginning with “$”, followed by an identifier. An identifier is composed
of an underscore or a letter followed by zero or more letters, digits, or underscores.
Identifiers may follow the “$” symbol directly, or follow the “$” enclosed in braces
“{}”. An identifier must be enclosed in braces if any letter, digit, or underscore that
is not part of the identifier immediately follows the identifier. Otherwise, the
following text will be interpreted as part of the identifier. You can examine any
shell variables defined for your environment by using the UNIX env command.
Positional shell variables, such as $1, $2, and so on, are not supported. Neither are
special shell variables, such as $@, $*, and so on.
To illustrate how shell variables work, consider the shell variable “S”, defined to be
the string “soft”. Suppose you wanted to use the shell variable to reference the
directory “/users/softkey”. The reference “/users/${S}key” would produce the
desired directory name. However, the reference “/users/$Skey” would cause the
shell variable “Skey” to be searched for.
Chapter 3: Using the Emulator/Analyzer Interface
Creating and Executing Command Files
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