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AtomicInteger lazySet vs. set

...GCable. In such cases, you can get better performance by avoiding the costs of the null volatile-write. There are a few other use cases along these lines for non-reference-based atomics as well, so the method is supported across all of the AtomicX classes. For people who like to think...
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Permission denied (publickey) when deploying heroku code. fatal: The remote end hung up unexpectedly

...ending SSH2_MSG_KEXDH_INIT debug1: expecting SSH2_MSG_KEXDH_REPLY debug1: Host 'heroku.com' is known and matches the RSA host key. debug1: Found key in /c/Wrong/Directory/.ssh/known_hosts:1 debug1: ssh_rsa_verify: signature correct debug1: SSH2_MSG_NEWKEYS sent debug1: expecting SSH2_MSG_NEWKEYS deb...
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Detect the Internet connection is offline?

... You can determine that the connection is lost by making failed XHR requests. The standard approach is to retry the request a few times. If it doesn't go through, alert the user to check the connection, and fail gracefully. Sidenote: To put the entire application i...
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Right query to get the current number of connections in a PostgreSQL DB

... Those two requires aren't equivalent. The equivalent version of the first one would be: SELECT sum(numbackends) FROM pg_stat_database; In that case, I would expect that version to be slightly faster than the second one, simp...
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How can I recover the return value of a function passed to multiprocessing.Process?

...argument, ). Note the , comma here! Or else Python will complain "missing positional arguments". Took me 10 minutes to figure out. Also check the manual usage (under the "process class" section). – yuqli Apr 29 '19 at 15:17 ...
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PowerShell script to return versions of .NET Framework on a machine?

... 4.0 (if you have them both installed): Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' -recurse | Get-ItemProperty -name Version,Release -EA 0 | Where { $_.PSChildName -match '^(?!S)\p{L}'} | Select PSChildName, Version, Release Based on the MSDN article, you could build a looku...
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Can not connect to local PostgreSQL

...les and have user permissions just like any other. It looks as though the OSX user attempting to access the database does not have file permissions to access the socket file. To confirm this I've done some tests on Ubuntu and psql to try to generate the same error (included below). You need to ch...
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How can I use grep to show just filenames on Linux?

...t is searched, a pathname of (standard input) will be written, in the POSIX locale. In other locales, standard input may be replaced by something more appropriate in those locales. You also do not need -H in this case. ...
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Programmatically Request Access to Contacts

Since updating to iOS 6 I've noticed that my code to add a contact to iPhone's address book no longer works. I believe this is a permission related problem, since Apple now requires user permission before accessing contacts (fixing this issue). ...
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When to use enumerateObjectsUsingBlock vs. for

...ificantly slower than fast enumeration for arrays and sets. I wonder why? iosdevelopertips.com/objective-c/… – Bob Spryn Feb 23 '14 at 2:20 2 ...