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POEnvironment Variables in Python on Linux
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copied!<p>Python's access to environment variables does not accurately reflect the operating system's view of the processes environment.</p> <p>os.getenv and os.environ do not function as expected in particular cases.</p> <p>Is there a way to properly get the running process' environment?</p> <hr> <p>To demonstrate what I mean, take the two roughly equivalent programs (the first in C, the other in python):</p> <pre><code>#include <stdio.h> #include <stdlib.h> #include <unistd.h> int main(int argc, char *argv[]){ char *env; for(;;){ env = getenv("SOME_VARIABLE"); if(env) puts(env); sleep(5); } } </code></pre> <hr> <pre><code>import os import time while True: env = os.getenv("SOME_VARIABLE") if env is not None: print env time.sleep(5) </code></pre> <hr> <p>Now, if we run the C program and attach to the running process with gdb and forcibly change the environment under the hood by doing something like this:</p> <pre><code>(gdb) print setenv("SOME_VARIABLE", "my value", 1) [Switching to Thread -1208600896 (LWP 16163)] $1 = 0 (gdb) print (char *)getenv("SOME_VARIABLE") $2 = 0x8293126 "my value" </code></pre> <p>then the aforementioned C program will start spewing out "my value" once every 5 seconds. The aforementioned python program, however, will not.</p> <p>Is there a way to get the python program to function like the C program in this case?</p> <p>(Yes, I realize this is a very obscure and potentially damaging action to perform on a running process)</p> <p>Also, I'm currently using python 2.4, this may have been fixed in a later version of python.</p>

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