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What is an OS kernel ? How does it differ from an operating system? [closed]
...ernel is an operating system in that sense.
The end-user definition is usually something around "a software package that provides a desktop, shortcuts to applications, a web browser and a media player". A kernel doesn't match that definition.
So for an end-user a Linux distribution (say Ubuntu) is...
What is the difference between the kernel space and the user space?
...
The really simplified answer is that the kernel runs in kernel space, and normal programs run in user space. User space is basically a form of sand-boxing -- it restricts user programs so they can't mess with memory (and other reso...
Check to see if python script is running
...cleanly, and check for it when you start up.
#/usr/bin/env python
import os
import sys
pid = str(os.getpid())
pidfile = "/tmp/mydaemon.pid"
if os.path.isfile(pidfile):
print "%s already exists, exiting" % pidfile
sys.exit()
file(pidfile, 'w').write(pid)
try:
# Do some actual work her...
Understanding Apache's access log
...the client IP)
%l is the identity of the user determined by identd (not usually used since not reliable)
%u is the user name determined by HTTP authentication
%t is the time the request was received.
%r is the request line from the client. ("GET / HTTP/1.0")
%>s is the status code sent from the s...
What is __init__.py for?
...kages as they existed in Python 3.2 and earlier. A regular package is typically implemented as a directory containing an __init__.py file. When a regular package is imported, this __init__.py file is implicitly executed, and the objects it defines are bound to names in the package’s namespace. The...
How do I correctly clean up a Python object?
...it close() statement is that you have to worry about people forgetting to call it at all or forgetting to place it in a finally block to prevent a resource leak when an exception occurs.
To use the with statement, create a class with the following methods:
def __enter__(self)
def __exit__(self...
How can I find where Python is installed on Windows?
I want to find out my Python installation path on Windows. For example:
19 Answers
19
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What does if __name__ == “__main__”: do?
...ngs:
it sets a few special variables like __name__, and then
it executes all of the code found in the file.
Let's see how this works and how it relates to your question about the __name__ checks we always see in Python scripts.
Code Sample
Let's use a slightly different code sample to explore ho...
When to use os.name, sys.platform, or platform.system?
...specific modules are available (e.g. posix, nt, ...)
platform.system() actually runs uname and potentially several other functions to determine the system type at run time.
My suggestion:
Use os.name to check whether it's a posix-compliant system.
Use sys.platform to check whether it's a linux,...
How to check BLAS/LAPACK linkage in NumPy and SciPy?
... Given its widespread usefulness, numpy.__config__ should really be a public API. Nonetheless, you win this round, davost.
– Cecil Curry
Feb 5 '16 at 5:51
2
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