Lantronix EMG 8500 EMG User Guide - Page 257

Interface Script Syntax, Table 12-4, Interface Script Syntax Definitions

Page 257 highlights

12: Scripts Interface Script Syntax This section describes the abbreviated scripting syntax for Interface Scripts. This limited syntax was created to prevent the creation of scripts containing potentially harmful commands. Script commands are divided into three groups: Primary, Secondary and Control Flow. Primary commands provide the basic functionality of a script and are generally the first element on a line of a script, as in: send_user "Password:" Secondary commands provide support for the primary commands and are generally not useful by themselves. For example, the expr command can be used to generate a value for a set command. set [expr 1 + 1] Control Flow commands allow conditional execution of other commands based on the results of the evaluation of a Boolean expression. Table 12-4 Interface Script Syntax Definitions Term Definition Word A contiguous group of characters delimited on either side by spaces. Not enclosed by double quotes. Primary Command One of the primary commands listed in this section. Secondary Command One of the secondary commands defined in this section. Quoted String A group of characters enclosed by double quote (") characters. A quoted string may include any characters, including space characters. If a double quote character is to be included in a quoted string it must be preceded (escaped) by a backslash character ('\'). Variable Reference A word (as defined above) preceded by a dollar sign character ('$'). CLI Command A quoted string containing a valid CLI show command. Arithmetic Operator A single character representing a simple arithmetic operation. The character may be one of the following:  A plus sign (+) representing addition  A minus sign (-) representing subtraction  An asterisk sign (*) representing multiplication  A forward slash (/) representing division  A percent sign (%) representing a modulus Boolean Expression An expression which evaluates to TRUE or FALSE. A Boolean expression has the following syntax: Each can be either a word or a variable reference. Boolean Operator A binary operator which expresses a comparison between two operands and evaluates to TRUE or FALSE. The following Boolean operators are valid:  '' greater than  '=' greater than or equal to  '==' equal to  '!=' not equal to EMG™ Edge Management Gateway User Guide 257

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12: Scripts
EMG™ Edge Management Gateway User Guide
257
Interface Script Syntax
This section describes the abbreviated scripting syntax for Interface Scripts. This limited syntax
was created to prevent the creation of scripts containing potentially harmful commands. Script
commands are divided into three groups: Primary, Secondary and Control Flow.
Primary commands provide the basic functionality of a script and are generally the first element on
a line of a script, as in:
send_user "Password:"
Secondary commands provide support for the primary commands and are generally not useful by
themselves. For example, the
expr
command can be used to generate a value for a
set
command
.
set <my_var> [expr 1 + 1]
Control Flow
commands allow conditional execution of other commands based on the results
of the evaluation of a Boolean expression.
Table 12-4
Interface Script Syntax Definitions
Term
Definition
Word
A contiguous group of characters delimited on either side by spaces. Not enclosed
by double quotes.
Primary Command
One of the primary commands listed in this section.
Secondary Command
One of the secondary commands defined in this section.
Quoted String
A group of characters enclosed by double quote (") characters. A quoted string
may include any characters, including space characters. If a double quote
character is to be included in a quoted string it must be preceded (escaped) by a
backslash character ('\').
Variable Reference
A word (as defined above) preceded by a dollar sign character ('$').
CLI Command
A quoted string containing a valid CLI
show
command.
Arithmetic Operator
A single character representing a simple arithmetic operation. The character may
be one of the following:
A plus sign (+) representing addition
A minus sign (-) representing subtraction
An asterisk sign (*) representing multiplication
A forward slash (/) representing division
A percent sign (%) representing a modulus
Boolean Expression
An expression which evaluates to TRUE or FALSE. A Boolean expression has the
following syntax:
<value> <Boolean operator> <value>
Each can be either a word or a variable reference.
Boolean Operator
A binary operator which expresses a comparison between two operands and
evaluates to TRUE or FALSE. The following Boolean operators are valid:
'<' less than
'>' greater than
'<=' less than or equal to
'>=' greater than or equal to
'==' equal to
'!=' not equal to