TACL Reference Manual

The TACL Environment
HP NonStop TACL Reference Manual—429513-018
6-2
Starting a TACL Process
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TACLBASE, an edit file that contains the same functionality as TACLSEGF. This
file resides on the same subvolume as the TACL file. Along with providing
functionality, TACLBASE provides a readable source of examples of TACL
programs.
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TACLCOLD, a segment file that TACL uses when running as the coldload
command interpreter. TACL creates this file or reuses it as a way of reducing the
chance that the coldload TACL will fail due to lack of disk space at startup.
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CPRULES0 and CPRULES1, which define the character set in use by TACL.
CPRULES0 is the default set.
In addition to the preceding list of files, there are utility programs that assist TACL in
performing certain operations. Each program is in a separate program file in
$SYSTEM.SYSnn or $SYSTEM.SYSTEM. These programs:
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Perform privileged operations, such as establishing user IDs and passwords or
reloading processors
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Must be licensed for use by nonprivileged users
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Can run only on the local system
Utility programs are listed in Section 8, UTILS:TACL Commands and Functions.
TACL requires the TACL program file and the TACLINIT file. If TACLBASE and
TACLSEGF are not present, TACL can operate, but will provide only built-in functions
and variables.
If TACLLOCL is missing, an unfriendly user could create a file with that name and
place harmful commands (such as PURGE commands) in it. To minimize this danger,
TACL creates a dummy TACLLOCL file whenever any user logs on and TACLLOCL is
not present. TACL secures the file to “NUUU” and gives it to the owner of the TACL
process itself.
A similar danger exists if your TACLCSTM file is missing, so TACL creates a dummy
TACLCSTM file when you log on and TACLCSTM is not present. TACL secures the file
to your default security and gives ownership of the file to you.
Starting a TACL Process
To start an interactive TACL process, run TACL with the IN and OUT files specified as
the same name, that of a terminal device. System management usually starts a TACL
process pair for each terminal, using the RUN or TACL command or the
#NEWPROCESS built-in function.
A TACL process:
Note. All TACL built-ins are executed by the TACL process, which runs only on the node
where it was started, regardless of any SYSTEM commands that are issued. To execute a
built-in command on another system, you must start a new TACL process on that system.