Question

I’m writing a python program that will spawn a subprocess to basically clone a log file. I have working code in 2.7, but because of vendor restrictions, I am forced to use Python 2.3, so using the subprocess module is out of the question.

I need help translating this:

self.FILE_OUT =  open(self.file2write,"a" )
self.FILE_IN=subprocess.Popen( self.file2process,
               stdout=self.FILE_OUT,
               bufsize=0,
               shell=True)

into 2.3 code.

I’m confused as to how to do the stdout=self.FILE_OUT.

Answer 1

It depends on what you’re doing, but the old way of executing commands was to use os.popen. It works like this:

>>> echo_stdout = os.popen('echo foo', 'r')
>>> echo_stdout.read()
'foo\n'

There are other versions of popen in the os module that do things like return a 2-tuple containing stdin and stdout, or a 3-tuple containing stdin, stdout, and stderr. See the docs for more details, and let me know if this doesn’t help.

Here’s an example of how to use popen2:

>>> cat_stdin, cat_stdout = os.popen2('cat')
>>> cat_stdin.write('foo\n')
>>> cat_stdin.close()
>>> cat_stdout.read()
'foo\n'