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Shell (ksh), and Bourne Again Shell (bash). Other kinds of UNIX shell are part of the C
Shell families.
When each command
is correctly
typed and entered
by pressing
RETURN
button,
signal
will
be
sent
to
the
shell
and
notify
it
to
interpret
the
command. In
most
cases, the shell
looks
for the appropriate software to run the command, by looking
up the
exact paths to the preset program directories. If it is found, the shell asks over the kernel
to
run
the command, otherwise
it
gives error
message.
The shell
will
then
wait
for
the
kernel
until command is
completely done. When
it
is
time,
shell displays a
prompt
line,
meaning
it is ready to get another command to enter. Every time the shell
is asked to run
commands,
it actually
calls
up another
shell
process
to
run
it. Snort
is
currently
one of
the
UNIX-friendly
applications that can be
setup and
run
through
the
UNIX
command
prompt easily.
2.1.4.3 Scripting Language
System administrators usually are able to make scripts
for specific administrative
tasks
related
to
their
job
in
managing
system.
Those
sets
of
commands
in
scripts
are
usually
called
scripting
language. Scripting language
is
different
from
programming
language,
as
the
programming
language
primarily
uses
compilers
to
run
the
program.
Compilers are
used
to translate source code
from
source computer to
create an
executable
program
into
another
computer
or
machine
language.
On
other
words,
the
code
is
translated
to
set
of
language
that
is
represented
in
binary
numbers.
Scripting
utilizes
interpreters
to
run
it.
Interpreter
is
a
program
that
executes
other
programs
or
scripts. Though both do
not have distinct ways
in running program, interpreter basically
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