After TCL installed on the machine, TCL information got

registred in the machine.

e.g:In Windows Registry

[HKEY_LOCAL_MACHINESOFTWAREActiveStateActiveTcl]

The TCL path is updated in Machine environment.

e.g:

PATH=C:/Tcl/bin;%PATH%

Then TCL starts working.

1.TCL a Scripting Language. TCL binary comes with

name "tclsh".

When we use TCL,[ For example from Command prompt/Terminal

try to run tclsh ] it provides default prompt "%" to User

and asks for input.

#tclsh

%

How TCL works??

---------------

Each input from user is treated as TCL command.

After providing the command, tclsh fetch(gets) that command

and try to validate/compile/execute and populate(puts) the

message.

#tclsh

% hello

invalid command name "hello"

% set

wrong # args: should be "set varName ?newValue?"

%set say "Hello"

Hello

2. When we use TCL, we can provide a Script file as

argument.

Example: Create a file "HelloTickle.tcl" containing:

set say "Hello"

puts $say

Execute:

#tclsh HelloTickle.tcl

Hello

How TCL works??

---------------

Tcl takes the Argument as a file and try to read the file.

TCL stores the file in memory and reads the file Line by

Line and try to validate/compile.

TCL provides the output and release the memory.

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