TACL Reference Manual

Overview of TACL
HP NonStop TACL Reference Manual—429513-018
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Language Features
This manual describes TACL syntax and semantics. For more information about how
to use TACL for specific programming tasks, see the TACL Programming Guide.
Language Features
TACL provides a set of predefined commands, functions, and data variables. These
entities are built into the TACL language and are the building blocks with which you
construct TACL programs:
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TACL built-in functions are intended for use in TACL programs. Built-in function
names start with a number sign (#). Most functions return a result that can be
analyzed programmatically. Examples include:
Built-in functions also provide flow control, such as loop control and exit
mechanisms. To see a list of functions, use the #BUILTINS built-in function or see
Section 9, Built-In Functions and Variables.
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TACL built-in variables contain information about the TACL environment. Built-in
variable names start with a number sign (#). These variables are used primarily to
establish the TACL environment. You can set and retrieve their values, and create
new instances of these variables, but you cannot delete the variables themselves.
Examples of these variables include:
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TACL commands (such as RUN and STOP) are intended for interactive use, but
you can use them in TACL programs. Commands do not return status or error
information; they usually display results.
TACL provides these procedural features:
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Data structures. TACL supports text and STRUCT variables.
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Data types. TACL interprets text variables as text unless you request an
arithmetic or logical operation. TACL supports an extensive set of data types
for STRUCT variables and for arguments to routine variables. Programs. TACL
programs allow you to define a block of TACL statements that performs one or
more tasks. You can access a TACL program from other TACL programs; you
can nest programs within other programs. For a description of TACL programs,
see Section 5, Statements and Programs.
#ARGUMENT Parses the arguments passed to a routine
#INPUT Reads information from the TACL IN file
#PROCESSINFO Returns information about a process
#OUT The name of the OUT file used by TACL
#PMSG The state of the PMSG flag
When set, TACL displays a message whenever
processes associated with your TACL process start and
stop.
#MYTERM The name of the home terminal