How to cat a file in this OS module example

Question

I need to cat a file inside the OS module of python.

What I'm trying to do is what I have accomplished in Perl. Please note the cat /tmp/illinois.txt

my $cmd = `$ENV{BB} $ENV{BBDISP} "status $host.$test $COLOR \`date\` 
\`cat /tmp/illinois.txt\`"`;

I would like to do the same thing in python.

cmd = "{BB} {BBDISP} \"status {NODE}.{TEST} {COLOR} {NOW}\n {MSG}\n\"".format(
TEST = "gov-affairs-MemoryUtilization",
BB = os.environ["BB"],
BBDISP = os.environ["BBDISP"],
COLOR = COLOR,
NOW = datetime.datetime.now(),
MSG=`cat /tmp/illinois.txt\`,
NODE="xxxxx")

Fire · Answer 1 · 2018-05-29T19:36:28.267

1

You can use the subprocess module to run commands from your script:

subprocess.run(cmd.split())

The run() function also takes parameters like shell=True if you want to keep the environment variables or stdout=subprocess.PIPE if you want to retreive the output of the command.

Honestly, just take a look at the docs ;)

EDIT: as Alan mentionned, the shell=True option is often considered not desirable, as you cannot be sure which shell is used by the system. More details here.

edited May 29 '18 at 19:36

answered May 29 '18 at 19:30

Fire

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I'd suggest you add that using `shell=True` is considered to be less desirable. – Alan May 29 '18 at 19:32
The subprocess.run() function only exists in Python 3.5 and newer. – BioRod May 29 '18 at 21:03

How to cat a file in this OS module example

1 Answers1