./configure options

When building packages, often we need to run ./configure with a bunch of options to build the package. To find out what the last options were used for configure, use this command:

./config.status --config

How to remember ./configure script arguments a year later

Execute a command, display output and get it's return code in Python

Often in my tests, I need to display the output and use the return code of the command I want to run. But I can't use check_output because my tests need to support RHEL6 and RHEL7 and RHEL6 is still on python 2.6.x and check_output is only available in Python 2.7

The following code snippet is modified from another website:

from subprocess import Popen, PIPE

 

cmd = "blah blah"

process = Popen(cmd.split(), stdout=PIPE)

process.communicate()    # execute it, the output goes to the stdout

exit_code = process.wait() # when finished, get the exit code

Access Environment Vars in Python

To access environment variables in Python, import os module and run the following command

import os
print os.environ['ENV_VAR_YOU_WANT']