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How to make a Python script run like a service or daemon in Linux
I have written a Python script that checks a certain e-mail address and passes new e-mails to an external program. How can I get this script to execute 24/7, such as turning it into daemon or service in Linux. Would I also need a loop that never ends in the program, or can it be done by just havin...
Is double square brackets [[ ]] preferable over single square brackets [ ] in Bash?
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[[ has fewer surprises and is generally safer to use. But it is not portable - POSIX doesn't specify what it does and only some shells support it (beside bash, I heard ksh supports it too). For example, you can do
[[ -e $b ]]
to test whether a ...
Simulate airplane mode in iPhone Simulator
... emulate the iPhone; it's just an environment for Mac apps to link against and look like an iPhone. So you need a way, at the system layer, to restrict an app from talking to the network. Unix doesn't provide that; it would almost certainly need kernel support to get it. You could do it more easily ...
What is a dependency property?
...cy properties are properties of classes that derive from DependencyObject, and they're special in that rather than simply using a backing field to store their value, they use some helper methods on DependencyObject.
The nicest thing about them is that they have all the plumbing for data binding bui...
Freeing up a TCP/IP port?
...on that port. The easiest way to do that would be to use the fuser(1) command. For example, to see all of the processes listening for http requests on port 80 (run as root or use sudo):
# fuser 80/tcp
If you want to kill them, then just add the -k option.
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cmake and libpthread
I'm running RHEL 5.1 and use gcc .
3 Answers
3
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Calling constructor from other constructor in same class
...cal instance of Lens which goes out of scope at the end of the constructor and is NOT assigned to "this". You need to use the constructor chaining syntax in Gishu's post to achieve what the question asks.
– Colin Desmond
May 6 '09 at 14:31
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Rails has_many with alias name
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FYI: this also works for has_and_belongs_to_many associations, only no need for the "foreign_key" piece
– David Moritz
Jun 6 '18 at 21:04
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Recommended method for escaping HTML in Java
Is there a recommended way to escape < , > , " and & characters when outputting HTML in plain Java code? (Other than manually doing the following, that is).
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How do I create a unique constraint that also allows nulls?
...er below.
Prior to SQL Server 2008
You cannot create a UNIQUE constraint and allow NULLs. You need set a default value of NEWID().
Update the existing values to NEWID() where NULL before creating the UNIQUE constraint.
s...