Simple shell scripting question: set name of directory using variable?

Question

Here's a very simple, probably duplicate (sorry - I have tried searching) shell scripting question.

What's the correct syntax to set DATA_DIR as a subdirectory of WDM_DIR, in the script below? (Line 2.)

WDM_DIR='/Users/ap257/wdm/wdm'
DATA_DIR=$WDM_DIR+/wdm/pylons_data/getdata/
cd $DATA_DIR

The point is that people can change WDM_DIR to whatever path is right for their system, but DATA_DIR is always in the same place relative to it.

Gopi · Accepted Answer · 2010-08-03 02:40:30Z

3

Here is the correct syntax

WDM_DIR=/Users/ap257/wdm/wdm
DATA_DIR=${WDM_DIR}/wdm/pylons_data/getdata/
cd -- "$DATA_DIR"

Well the syntax may vary a bit depending on what shell you are using.

edited Aug 3, 2010 at 2:40

answered Aug 2, 2010 at 16:02

Gopi

10.3k4 gold badges33 silver badges47 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Gilles 'SO- stop being evil' Over a year ago

The last line should be cd -- "$DATA_DIR". The -- is in case $WDM_DIR starts with a - (not a problem if you require an absolute path). The quotes are in case $WDM_DIR contains a special character such as whitespace. Rule 1 of shell scripting: Always put double quotes around variable substitutions.

Gopi Over a year ago

@Gilles Thank you for the inputs. I have updated my answer with your suggestions.

Drakosha · Accepted Answer · 2010-08-02 16:02:12Z

0

The easy way is:

DATA_DIR="${WDM_DIR}/wdm/pylons_data/getdata/"

answered Aug 2, 2010 at 16:02

Drakosha

12.2k4 gold badges42 silver badges52 bronze badges

Collectives™ on Stack Overflow

Simple shell scripting question: set name of directory using variable?

2 Answers 2

2 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related