Changing PATHS
 

Hi,

Im having problems installing the program NS2. After ive installed it , it asks to do the following :-

Please put
/usr/src/ns-allinone-2.27/bin:/usr/src/ns-allinone-2.27/tcl8.4.5/unix
:/usr/src/ns-allinone-2.27/tk8.4.5/unix
into your PATH environment; so that you'll be able to
run itm/tclsh/wish/xgraph.

IMPORTANT NOTICES:

(1) You MUST put /usr/src/ns-allinone-2.27/otcl-1.8,
/usr/src/ns-allinone-2.27/l
ib,
into your LD_LIBRARY_PATH environment variable.
If it complains about X libraries, add path to
your X libraries
into LD_LIBRARY_PATH.
If you are using csh, you can set it like:
setenv LD_LIBRARY_PATH <paths>
If you are using sh, you can set it like:
export LD_LIBRARY_PATH=<paths>

(2) You MUST put
/usr/src/ns-allinone-2.27/tcl8.4.5/library into your
TCL_LIBRAR
Y environmental
variable. Otherwise ns/nam will complain during
startup.

(3) [OPTIONAL] To save disk space, you can now delete
directories tcl8.4.5
and tk8.4.5. They are now installed under
/usr/src/ns-allinone-2.27/{bin,inc
lude,lib}

After these steps, you can now run the ns validation
suite with
cd ns-2.27; ./validate

Ive run the followigng command : export $PATH = usr/src/ns-allinone-2.27/bin:/usr/src/ns-allinone-2.27/tcl8.4.5/unix
:/usr/src/ns-allinone-2.27/tk8.4.5/unix but it doesnt seem to have worked. Could anyone tell me the correct procedures as in the right coding so i can copy it in terminal (im sorry at the laziness but ive been trying this for the past month and am still getting wrong).
Also for future refrence is there a book or website which explains these types of things?

Please help.

There are plenty tutorials on shell scripting and syntax.

but, if you want to extend your users path, add this to your /home/user .bashrc file.
example.

PATH=/home/whateverdirectory/directory
export PATH

export PATH=$PATH:/usr/src/ns-allinone-2.27/bin:/usr/src/ns-allinone-2.27/tcl8.4.5/unix
:/usr/src/ns-allinone-2.27/tk8.4.5/unix

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/src/ns-allinone-2.27/otcl-1.8,
/usr/src/ns-allinone-2.27/lib

Hi Autopsy,
What i dont understand (coming from a windows background) what changing paths entail. Is it pointing to a particular area? Is it moving some directories into the scope of the computer? what does it do?
Sorry if its really basic.

When you type a program name you'd like to run without the full path, all directories in PATH are searched to find an executable file with the name you provided. If it's found - it's started.

That was really great
 

Mara,
You are really doing a good job by writing tips for us. It is really useful when i installed ns2 nd when i was searching to find some help.
Thank you so much.
Kind regards
Shyaam