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EC2 instance has no public DNS
A guy I work with gave me the EC2 credentials to log onto his EC2 console. I was not the one who set it up. Some of the instances show a public dns name and others have a blank public DNS. I want to be able to connect to the instances that have a blank public DNS. I have not been able to figure out ...
`date` command on OS X doesn't have ISO 8601 `-I` option?
In a Bash script, I want to print the current datetime in ISO 8601 format (preferably UTC), and it seems that this should be as simple as date -I :
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accepting HTTPS connections with self-signed certificates
I'm trying to make HTTPS connections, using HttpClient lib, but the problem is that, since the certificate isn't signed by a recognized Certificate Authority (CA) like Verisign , GlobalSIgn , etc., listed on the set of Android Trusted Certificates, I keep getting javax.net.ssl.SSLException: Not ...
Rails Observer Alternatives for 4.0
With Observers officially removed from Rails 4.0 , I'm curious what other developers are using in their place. (Other than using the extracted gem.) While Observers were certainly abused and could easily become unwieldily at times, there were many use-cases outside of just cache-clearing where they...
How do I convert a IPython Notebook into a Python file via commandline?
I'm looking at using the *.ipynb files as the source of truth and programmatically 'compiling' them into .py files for scheduled jobs/tasks.
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Mismatch Detected for 'RuntimeLibrary'
I downloaded and extracted Crypto++ in C:\cryptopp. I used Visual Studio Express 2012 to build all the projects inside (as instructed in readme), and everything was built successfully. Then I made a test project in some other folder and added cryptolib as a dependency. After that, I added the includ...
jQuery hasClass() - check for more than one class
With:
13 Answers
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How can I make PHP display the error instead of giving me 500 Internal Server Error [duplicate]
This has never happened before. Usually it displays the error, but now it just gives me a 500 internal server error. Of course before, when it displayed the error, it was different servers. Now I'm on a new server (I have full root, so if I need to configure it somewhere in the php.ini, I can.) Or p...
How to stop a program running under Eclipse?
I can't find an option to stop a running program (whether in debug or release mode).
9 Answers
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Is there a good reason I see VARCHAR(255) used so often (as opposed to another length)?
In multiple courses, books, and jobs, I have seen text fields defined as VARCHAR(255) as kind of the default for "shortish" text. Is there any good reason that a length of 255 is chosen so often, other than being a nice round number ? Is it a holdout from some time in the past when there was a go...