Executing python scripts sequentially using subprocess.Popen

Question

I am using python's subprocess for executing scripts against a C code base. Concretely, I have a number of scripts that I run one by one against a single instantiation of a program. Here is what I want to do:

start process ABC

execute python scripts 01 against ABC and store output from ABC in file A

execute python scripts 02 against ABC and store output from ABC in file B

execute python scripts 03 against ABC and store output from ABC in file C

My current scheme with

myProcess = subprocess.Popen(PATH, BUFFSIZE, STDOUT= myFilePointer ...)

But this fails to yield return output from each execution of process ABC and only records output in case of script 01 and not the rest.

I have looked at official documentation and other resources but cannot find.

Answer 1

Try this:

 cmd = subprocess.Popen("ABC %s" % command,
                    stdout=out,
                    stderr=subprocess.PIPE)
 stdout, stderr = cmd.communicate()
 retcode = cmd.returncode

Use command parameter to pass command line argument to ABC. After execution of Popen output from ABC will be stored in stdout . Error that might occur are stored to stderr .