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Functions

Find out the starting directory of a script

Terminal - Find out the starting directory of a script
echo "${0%/*}"
2011-04-17 12:09:56
User: mhs
Functions: echo
10
Find out the starting directory of a script

Invoked from within a shell script, this will print the directory in which the script resides. Doesn't depend on external tools, /proc/self/*, etc.. (`echo` is a shell builtin.) To see the *current working* directory of a script, use `pwd`.

Alternatives

There are 5 alternatives - vote for the best!

Terminal - Alternatives
eval ls -l /proc/{$(pgrep -d, COMMAND)}/cwd
2011-04-14 13:41:58
User: splante
Functions: eval ls
3

This is an alternative to another command using two xargs. If it's a command you know there's only one of, you can just use:

ls -l /proc/$(pgrep COMMAND)/cwd
echo COMMAND | xargs -ixxx ps -C xxx -o pid= | xargs -ixxx ls -l /proc/xxx/cwd
readlink /proc/self/cwd
mydir=$(cd $(dirname ${BASH_SOURCE:-$0});pwd)
2011-04-27 16:33:38
User: xeor
Functions: cd dirname
Tags: cd script pwd
0

I submitted a command like this without $0 if $BASH_SOURCE is unset. Therefor, it did only work when using ./script, not using 'sh script'. This version handles both, and will set $mydir in a script to the current working directory. It also works on linux, osx and probably bsd.

pwdx $(pgrep command)
2013-02-01 08:33:15
User: weidenrinde
0

The pwdx command reports the current working directory of a process or processes.

Know a better way?

If you can do better, submit your command here.

What others think

Being lazy I use

pwd

although

echo $PWD

would work as well.

Comment by penpen 176 weeks and 2 days ago

Bummer... Sorry, didn't read carefully enough. My bad...

Comment by penpen 176 weeks and 2 days ago

To be clear, I've edited the original post. `pwd` does indeed show the *current working directory*. This method (which uses shell special parameters) simply shows the *location* of the script.

Comment by mhs 176 weeks and 1 day ago

what does this do that:

dirname $0

doesn't?

Comment by tatsujin 175 weeks and 2 days ago

@tatsujin

Think you meant, "Doesn't this do that?"

Answer: Yes, although invoking a separate `dirname` process is slightly more expensive.

Comment by mhs 175 weeks and 1 day ago

This isn't meant to give present working directory (which you would already have in $PWD in sh or bash). Instead, this gives the directory of the script that was launched. It's more efficient than the the little fork of calling `/usr/bin/dirname $0`. I like it.

Comment by Mozai 174 weeks and 6 days ago

Your point of view

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