Use variable in call to subprocess

Question

I'm using Python in the build of a Qt application. The Python script gets called in different PCs and these PCs might have different number of CPUs. To take advantage of that, in the make step I 'm specifying the number of CPUs:

subprocess.call(["mingw32-make",
                 "-j4"], shell=True, env=environ)

To check the number of CPUs I do:

n = multiprocessing.cpu_count()

How do I replace the -j4 by n?

Padraic Cunningham · Accepted Answer · 2016-10-10T17:57:13.997

0

Pass it in using str.format:

n = multiprocessing.cpu_count()
subprocess.call(["mingw32-make", "-j{}".format(n)], env=environ)

edited Oct 10 '16 at 17:57

answered Oct 10 '16 at 17:44

Padraic Cunningham

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Need to remove the minus sign at the end of `subprocess.call(["mingw32-make", "-j{}".format(n)], env=environ) –` – Brian Oct 10 '16 at 17:56
And don't use `shell=True`. – tripleee Oct 10 '16 at 18:12
@Brian, which minus sign? – KcFnMi Oct 10 '16 at 18:34
It was removed. Random typo minus sign at the end of the line. – Brian Oct 10 '16 at 19:09

Use variable in call to subprocess

1 Answers1