How to reference a file for variables using Bash?
I want to call a settings file for a variable, how can I do this in bash?
So the settings file will define the variables (eg: CONFIG.FILE) :
production="liveschool_joe"
playschool="playschool_joe"
And the script will use those variables in it
#!/bin/bash
production="/REFERENCE/TO/CONFIG.FILE"
playschool="/REFERENCE/TO/CONFIG.FILE"
sudo -u wwwrun svn up /srv/www/htdocs/$production
sudo -u wwwrun svn up /srv/www/htdocs/$playschool
How can I get bash to do something like that? Will I have to use awk/sed etc...?
Solution 1:
The short answer
Use the source
command.
An example using source
For example:
config.sh
#!/usr/bin/env bash
production="liveschool_joe"
playschool="playschool_joe"
echo $playschool
script.sh
#!/usr/bin/env bash
source config.sh
echo $production
Note that the output from sh ./script.sh
in this example is:
~$ sh ./script.sh
playschool_joe
liveschool_joe
This is because the source
command actually runs the program. Everything in config.sh
is executed.
Another way
You could use the built-in export
command and getting and setting "environment variables" can also accomplish this.
Running export
and echo $ENV
should be all you need to know about accessing variables. Accessing environment variables is done the same way as a local variable.
To set them, say:
export variable=value
at the command line. All scripts will be able to access this value.
Solution 2:
even shorter using the dot:
#!/bin/bash
. CONFIG_FILE
sudo -u wwwrun svn up /srv/www/htdocs/$production
sudo -u wwwrun svn up /srv/www/htdocs/$playschool
Solution 3:
Use the source
command to import other scripts:
#!/bin/bash
source /REFERENCE/TO/CONFIG.FILE
sudo -u wwwrun svn up /srv/www/htdocs/$production
sudo -u wwwrun svn up /srv/www/htdocs/$playschool