Need help with setting up environment variables


 
Thread Tools Search this Thread
Top Forums UNIX for Dummies Questions & Answers Need help with setting up environment variables
# 1  
Old 01-21-2010
Bug Need help with setting up environment variables

hi all,
I would appreciate if some one could explain me the difference between setting up the variables as shown below

Code:
HOME=${HOME:-"/home/user1"}

Code:
HOME=/home/user1

# 2  
Old 01-21-2010
know your shell!

From the bash manpage (which you could have checked yourself ;-)) :

Quote:
${parameter:-word}
Use Default Values. If parameter is unset or null,
the expansion of word is substituted. Otherwise,
the value of parameter is substituted.
Nifty, ey? ;-)
 
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Setting environment variables from a file :

Hi, I have around 10 environment variables in my shell script. i want to set this all in a file and just call that file in my shell script. How can i do that ? Please help. TIA! (6 Replies)
Discussion started by: qwertyu
6 Replies

2. Shell Programming and Scripting

setting environment variables with space

Hi, I'm having problems setting environment variable that has space value. Below is my shell script. export LINE=$@ TO=`echo $LINE | awk '{print $1}'` CC=`echo $LINE | awk '{print $2}'` BC=`echo $LINE | awk '{print $3}'` echo "TO=$TO" echo "CC=$CC" echo "BC=$BC" echo "1=$1" echo... (5 Replies)
Discussion started by: adshocker
5 Replies

3. Shell Programming and Scripting

Setting environment variables in Cron file

Hi, In Cron file i'm using username and password hard-coded and now i wann to use environmental veraiables in cron file. But Could you please guide me how to use these environmental variables in cron file ? Thanks, Shyamu.A (4 Replies)
Discussion started by: shyamu544
4 Replies

4. Emergency UNIX and Linux Support

Problem setting environment variables from script

Hi all! I know that environment variables can be set on the .bashrc file, but I need to set them from a sh script. I saw a lot of websites that teach this but it doesn't work for me. #!/bin/sh DEKTOP=$DESKTOP=:/home/rrodrigues/Desktop export DESKTOP if I do echo $DESKTOP returns me... (10 Replies)
Discussion started by: ruben.rodrigues
10 Replies

5. UNIX for Dummies Questions & Answers

Setting up environment variables

Hi all, This is my first post here. I need to set up a few environment variables with a shell script. Some are hard-coded, but some should come from other commands or as input from the user. How do I do that? For example, I need to export a variable as such: export DISPLAY=127.0.0.1:8.0 ... (2 Replies)
Discussion started by: exchequer598
2 Replies

6. UNIX for Dummies Questions & Answers

Setting Environment Variables

#!/bin/bash if ; then ASS1_DATA_DIR=./ echo $ASS1_DATA_DIR export ASS1_DATA_DIR echo "data dir" fi if ; then ASS1_OUTPUT_DIR=./ export ASS1_OUTPUT_DIR fi I want to create a new environment variable ASS1_DATA_DIR and ASS1_OUTPUT_DIR in bash and set them to the current... (4 Replies)
Discussion started by: bigubosu
4 Replies

7. Shell Programming and Scripting

Help in Setting Environment variables in TCSH

Hello All, I am writing a script to set some environment variables which are required for a particular application. I understand that the environment variables set by Shell script can, at the max, be valid for the session. They will have to be set again once the session is closed and re-opened.... (1 Reply)
Discussion started by: kssandeep
1 Replies

8. Shell Programming and Scripting

Setting environment variables in Makefile

I've seen a few other threads like this, but they either went unanswered or failed to answer my question. How do I set an environment variable in a Makefile? What I'm trying to do is use GNU make to automate an ant build. In order to run ant, I've got to first set a few environment... (1 Reply)
Discussion started by: Bags
1 Replies

9. Shell Programming and Scripting

Setting up Environment Variables

Hi all, I am trying to set up some variables in a shell script. The variables contain values of various paths needed to run a java module. The problem is the variables dont seem to be setting at all. here is what i am trying to do : JAR_HOME=/home/was5/bdcms/scheduledjobs/lib export... (6 Replies)
Discussion started by: rpandey
6 Replies

10. UNIX for Dummies Questions & Answers

setting environment variables ???

Hello, I want to set some environment variables with this script: ip=$@ echo Remote Computer: $ip PERLDB_OPTS="CallKomodo=$ip:9000 RemotePort=$ip:9010 PrintRet=0" export PERLDB_OPTS PERL5LIB=/opt/komodo export PERL5LIB echo PERLDB_OPTS: $PERLDB_OPTS echo PERL5LIB: $PERL5LIB But it... (5 Replies)
Discussion started by: Gargamel
5 Replies
Login or Register to Ask a Question