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When is TCP option SO_LINGER (0) required?
...void large numbers of connections sitting in the TIME_WAIT state, tying up all the available resources on a server.
When a TCP connection is closed cleanly, the end that initiated the close ("active close") ends up with the connection sitting in TIME_WAIT for several minutes. So if your protocol i...
Does height and width not apply to span?
...ides no context to indicate that a div is inherently inappropriate semantically.
– Isaac
Mar 22 '10 at 9:45
1
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What are CN, OU, DC in an LDAP search?
...N = Common Name
OU = Organizational Unit
DC = Domain Component
These are all parts of the X.500 Directory Specification, which defines nodes in a LDAP directory.
You can also read up on LDAP data Interchange Format (LDIF), which is an alternate format.
You read it from right to left, the right-m...
Python 3 ImportError: No module named 'ConfigParser'
...s very buggy, it crashes at first execute call.
– if __name__ is None
Dec 30 '12 at 14:46
15
@Jan...
Convert to binary and keep leading zeros in Python
...ction in Python. However, it always removes the leading zeros, which I actually need, such that the result is always 8-bit:
...
Force R not to use exponential notation (e.g. e+10)?
...
This is a bit of a grey area. You need to recall that R will always invoke a print method, and these print methods listen to some options. Including 'scipen' -- a penalty for scientific display. From help(options):
‘scipen’: integer. A penalty to be applied wh...
Delete an element from a dictionary
... use an an already constructed dict without a single item as **kwargs, some_function(**{k:v for k,v in some_dict.items() if k not 'some_key'})
– Cole
Nov 19 '17 at 21:14
...
How to convert 2D float numpy array to 2D int numpy array?
...(int), np.array([-np.inf]).astype(int), and np.array([np.nan]).astype(int) all return the same thing. Why?
– BallpointBen
May 14 '18 at 20:47
1
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Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
...an work around it from within psql by executing the DDL statement conditionally:
SELECT 'CREATE DATABASE mydb'
WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'mydb')\gexec
The manual:
\gexec
Sends the current query buffer to the server, then treats each column of each row of the query's...
Why is creating a Thread said to be expensive?
... there is a fair bit of work involved:
A large block of memory has to be allocated and initialized for the thread stack.
System calls need to be made to create / register the native thread with the host OS.
Descriptors need to be created, initialized and added to JVM-internal data structures.
It...