Can I get the absolute path to the current script in KornShell?

Question

Is it possible to find out the full path to the script that is currently executing in KornShell (ksh)?

i.e. if my script is in /opt/scripts/myscript.ksh, can I programmatically inside that script discover /opt/scripts/myscript.ksh ?

Thanks,

score 27 · Accepted Answer · edited May 04 '10 at 00:44

27

You could use:

## __SCRIPTNAME - name of the script without the path
##
typeset -r __SCRIPTNAME="${0##*/}"

## __SCRIPTDIR - path of the script (as entered by the user!)
##
__SCRIPTDIR="${0%/*}"

## __REAL_SCRIPTDIR - path of the script (real path, maybe a link)
##
__REAL_SCRIPTDIR=$( cd -P -- "$(dirname -- "$(command -v -- "$0")")" && pwd -P )

edited May 04 '10 at 00:44

Jonathan Leffler

730,956
141
904
1,278

answered May 04 '09 at 11:16

Marnix

294
2
3

1

Great answer - I was hoping this would also work if you source the script i.e. '. /some/script.sh' but it doesn't. – synthesizerpatel Nov 22 '13 at 02:33
5

@synthesizerpatel: In ksh93, you have `${.sh.file}` which also works for sourced files. – Mat M Jun 04 '14 at 14:19
2

As pointed out by Gruik, this doesn't work if there is a symbolic link to the shell script itself. So if you link the command into, say, /usr/bin, then __REAL_SCRIPTDIR will return /usr/bin, which is (most likely) not what you want. You do apparently need readlink for this – Tom Quarendon Jan 27 '15 at 14:42

score 10 · Answer 2 · answered Jul 31 '13 at 17:40

10

In korn shell, all of these $0 solutions fail if you are sourcing in the script in question. The correct way to get what you want is to use $_

$ cat bar

echo dollar under is $_
echo dollar zero is $0

$ ./bar

dollar under is ./bar
dollar zero is ./bar

$ . ./bar
dollar under is bar
dollar zero is -ksh

Notice the last line there? Use $_. At least in Korn. YMMV in bash, csh, et al..

answered Jul 31 '13 at 17:40

This answer should be incorporated into the accepted one. I was struggling for half an hour sourcing my ksh script until I realized that I need `$_`. – andreee Dec 22 '16 at 09:13

score 9 · Answer 3 · edited Feb 07 '12 at 08:54

9

Well it took me a while but this one is so simple it screams.

_SCRIPTDIR=$(cd $(dirname $0);echo $PWD)

since the CD operates in the spawned shell with $() it doesn't affect the current script.

edited Feb 07 '12 at 08:54

musefan

47,875
21
135
185

answered Feb 07 '12 at 00:06

Mitch Brown

91
1
1

score 8 · Answer 4 · answered Apr 17 '09 at 11:55

8

How the script was called is stored in the variable $0. You can use readlink to get the absolute file name:

readlink -f "$0"

answered Apr 17 '09 at 11:55

soulmerge

73,842
19
118
155

thanks for the $0 tip, what's readlink? doesn't seem to be on my system – brabster Apr 17 '09 at 11:57
Hmmm need something totally within ksh, no dependencies. Thanks though – brabster Apr 17 '09 at 12:35
I'm afraid that won't be possible - unless ksh has a possibility I am not aware of for interacting with the file system. What's your OS? – soulmerge Apr 17 '09 at 13:06
3

`$0` refers to the name of the command as it was invoked, and does not need to refer to a file system object. – Henk Langeveld Aug 05 '12 at 09:06

score 4 · Answer 5 · edited Aug 26 '11 at 11:46

4

The variable $RPATH contains the relative path to the real file or the real path for a real file.

CURPATH=$( cd -P -- "$(dirname -- "$(command -v -- "$0")")" && pwd -P )

CURLOC=$CURPATH/`basename $0`

if [ `ls -dl $CURLOC |grep -c "^l" 2>/dev/null` -ne 0 ];then

    ROFFSET=`ls -ld $CURLOC|cut -d ">" -f2 2>/dev/null`

    RPATH=`ls -ld $CURLOC/$ROFFSET 2>/dev/null`

else

    RPATH=$CURLOC

fi

echo $RPATH

edited Aug 26 '11 at 11:46

arunkumar

32,803
4
32
47

answered Aug 25 '11 at 15:53

Edward Staudt

41
1

This does appear to be the only method available that copes with the situation of a symlink to the script itself, horrible though it is. – Tom Quarendon Jan 27 '15 at 14:45

score 2 · Answer 6 · edited Apr 23 '15 at 22:08

readlink -f would be the best if it was portable, because it resolves every links found for both directories and files.

On mac os x there is no readlink -f (except maybe via macports), so you can only use readlink to get the destination of a specific symbolic link file.

The $(cd -P ... pwd -P) technique is nice but only works to resolve links for directories leading to the script, it doesn't work if the script itself is a symlink

Also, one case that wasn't mentioned : when you launch a script by passing it as an argument to a shell (/bin/sh /path/to/myscript.sh), $0 is not usable in this case

I took a look to mysql "binaries", many of them are actually shell scripts ; and now i understand why they ask for a --basedir option or need to be launched from a specific working directory ; this is because there is no good solution to locate the targeted script

score 2 · Answer 7 · answered Jun 11 '10 at 13:51

2

This is what I did:

if [[ $0 != "/"* ]]; then
  DIR=`pwd`/`dirname $0`
else
  DIR=`dirname $0`
fi

answered Jun 11 '10 at 13:51

John Nilsson

17,001
8
32
42

score 1 · Answer 8 · answered Dec 07 '09 at 11:22

1

Try which command.

which scriptname

will give you the full qualified name of the script along with its absolute path

answered Dec 07 '09 at 11:22

Sachin

20,805
32
86
99

score 1 · Answer 9 · answered May 15 '09 at 19:42

1

This works also, although it won't give the "true" path if it's a link. It's simpler, but less exact.

SCRIPT_PATH="$(whence ${0})"

answered May 15 '09 at 19:42

mtruesdell

3,697
3
21
20

score 0 · Answer 10 · answered Jan 04 '16 at 14:58

I upgraded the Edward Staudt's answer, to be able to deal with absolute-path symbolic links, and with chains of links too.

DZERO=$0
while true; do
  echo "Trying to find real dir for script $DZERO"
  CPATH=$( cd -P -- "$(dirname -- "$(command -v -- "$DZERO")")" && pwd -P )
  CFILE=$CPATH/`basename $DZERO`
  if [ `ls -dl $CFILE | grep -c "^l" 2>/dev/null` -eq 0 ];then
    break
  fi
  LNKTO=`ls -ld $CFILE | cut -d ">" -f2 | tr -d " " 2>/dev/null`
  DZERO=`cd $CPATH ; command -v $LNKTO`
done

Ugly, but works... After run this, the path is $CPATH and the file is $CFILE

score -1 · Answer 11 · edited Nov 20 '11 at 00:18

-1

Try using this:

dir = $(dirname $0)

edited Nov 20 '11 at 00:18

animuson

53,861
28
137
147

answered May 04 '10 at 00:15

kailash

1

score -1 · Answer 12 · answered Sep 07 '17 at 14:35

-1

Using $_ provides the last command.

>source my_script

Works if I issue the command twice:

>source my_script
>source my_script

If I use a different sequence of commands:

>who
>source my_script

The $_ variable returns "who"

answered Sep 07 '17 at 14:35

JohnCanessa

39
6

Can I get the absolute path to the current script in KornShell?

12 Answers12

Linked