Generally, the utilization of Ns2 is functioning to implement the network components, links and etc. based on simulation environment through Tcl language. The implementation of events in scheduled time, simulation process, activation of events and event queue placement are regulated through the Ns2 event scheduler. Ns2 is capable to write the log based on simulation to trace the trace file and on the other hand, the Ns2 user is capable to analyze the simulation results through utilizing the trace files.
Starting Ns
While we start ns we have to use the command <tclscript>’ and it is the name of the Tcl script for the definition of simulation scenario. The ns have to be started without any arguments and through entering the Tcl commands in the Tcl shell. The Tcl commands include various commands and they are recognized through the news lines. For instance,
set b 15
set a 24
All the commands include the words in several number and the first word is considered as the name of the command. The arguments are denoted as the additional words with the commands. In addition, they are capable to proceed in the same line with the utilization of semi colon as the separator.
set a 24; set b 15
Files and Lists Using Tcl
set testfile [open test.dat r]
The above mentioned command is about to open the file and to read it in Tcl. The command that is used to store the file line of file is mentioned below.
gets $testfile list
Consequently, the elements are required to acquire the list of commands that are enlisted in the following.
set first [lindex $list 0]
set second [lindex $list 1]The following command is about the file that has to be written and that puts.
set testfile [open test.dat w]
puts $testfile “testi”Calling Subprocesses Using Tcl
The command exec is considered as the creation of subprocess and it is utilized as the exec which is similar to provide the command line to the shell program. Additionally, it is deployed to require the tcl script along with the value of parameter and that is highlighted in the below mentioned command.
exec rm $testfile
for {set ind 1} {$ind <= 10} {incr ind} {
set test $ind
exec ns example.tcl test
}
Until now, we have discussed the research significance about Tcl in Ns2. We hope that you have got the general idea to begin your research in with our experts. So, the research scholars can confidently reach out to us without any hesitation for all your research needs.