2008-03-14, 05:36(-07), Jeenu:
[...]
> where_am_i=$((cd $(dirname $0) && pwd))
>
> Or is there any other/easier way?

That's really an approximation.

where_am_i=$(
cd -P -- "$(dirname -- "$0")" && pwd -P
)

will work in most cases.

case where it may not work is if the script is started as:

sh myscript.sh

instead of just:

myscript.sh

and myscript.sh happens not to be in the current directory in
which case it's being looked up in $PATH. To work around that,
you can do something like:

where_am_i=$(
if [ -e "$0" ]; then
prog=$0
else
prog=$(command -v -- "$0") || exit
fi
cd -P -- "$(dirname -- "$prog")" && pwd -P
)

This may still be fooled if the script is not executable and
your shell is not standard compliant (like bash) and finds it in
$PATH. (sh myscript, if myscript doesn't exist in the current
directory is meant to search for an *executable* myscript in
$PATH, bash misses the "executable" requirement, and command -v
only reports executables).

It will also not work if the directory name ends in newline
characters.

--
Stéphane