Python's access to environment variables does not accurately reflect the operating system's view of the processes environment.
os.getenv and os.environ do not function as expected in particular cases.
Is there a way to properly get the running process' environment?
To demonstrate what I mean, take the two roughly equivalent programs (the first in C, the other in python):
#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);
}
}
import os
import time
while True:
env = os.getenv("SOME_VARIABLE")
if env is not None:
print env
time.sleep(5)
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:
(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"
then the aforementioned C program will start spewing out "my value" once every 5 seconds. The aforementioned python program, however, will not.
Is there a way to get the python program to function like the C program in this case?
(Yes, I realize this is a very obscure and potentially damaging action to perform on a running process)
Also, I'm currently using python 2.4, this may have been fixed in a later version of python.
