How to use os.system() to run `> >(tee -a log)`?

Question

I run the following command in the terminal.

sh -c "echo out; echo err 2>&1" >>(tee -a stdout.log) 2>>(tee -a stdout.log >&2)

output:

out  
err

Using os.system in Python will report an error.

import os
cmd = """
sh -c "echo out; echo err 2>&1" > >(tee -a stdout.log) 2> >(tee -a stdout.log >&2)
"""
os.system(cmd)

sh: -c: line 1: syntax error near unexpected token `>'
sh: -c: line 1: `sh -c "echo out" > >(tee -a stdout.log) 2> >(tee -a stdout.log >&2)'

Answer 1

>(...) is bash-specific syntax. Make that bash -c instead of sh -c .

Also you should enclose the entire command in quotes since -c expects a single argument.

cmd = """
bash -c 'echo out > >(tee -a stdout.log) 2> >(tee -a stdout.log >&2)'
"""

To test writing to both stdout and stderr like your original example, try like this with curly braces:

cmd = """
bash -c '{ echo out; echo err 2>&1; } > >(tee -a stdout.log) 2> >(tee -a stdout.log >&2)'
"""