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When should one use a spinlock instead of mutex?
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The Theory
In theory, when a thread tries to lock a mutex and it does not succeed, because the mutex is already locked, it will go to sleep, immediately allowing another thread to run. It will continue to sleep until being woken up, which will be the case once the mutex is being unlocke...
“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
... vast wisdom of the PHP Manual:
Relying on the default value of an uninitialized variable is problematic in the case of including one file into another which uses the same variable name. It is also a major security risk with register_globals turned on. E_NOTICE level error is issued in case of w...
How to run a shell script on a Unix console or Mac terminal?
I know it, forget it and relearn it again. Time to write it down.
7 Answers
7
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Redirect STDERR / STDOUT of a process AFTER it's been started, using command line?
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p dup2(open("/dev/null", 0), 1)
p dup2(open("/dev/null", 0), 2)
detach
quit
e.g.:
$ tail -f /var/log/lastlog &
[1] 5636
$ ls -l /proc/5636/fd
total 0
lrwx------ 1 myuser myuser 64 Feb 27 07:36 0 -> /dev/pts/0
lrwx------ 1 myuser myuser 64 Feb 27 07:36 1 -> /dev/pts/0
lrwx------ 1 my...
Prefer composition over inheritance?
Why prefer composition over inheritance? What trade-offs are there for each approach? When should you choose inheritance over composition?
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Python class inherits object
Is there any reason for a class declaration to inherit from object ?
6 Answers
6
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Templated check for the existence of a class member function?
Is it possible to write a template that changes behavior depending on if a certain member function is defined on a class?
2...
Is Chrome's JavaScript console lazy about evaluating arrays?
I'll start with the code:
7 Answers
7
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How can I launch multiple instances of MonoDevelop on the Mac?
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On Mac, if you have an app open and you try to launch it again, the Mac just switches to the open app. You can force it to open a new instance by passing the option "-n" to the launcher. In a terminal, run
open -n /Applications/MonoDevelop.app
Note also that MonoDevelop is ca...
How to make a .jar out from an Android Studio project
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Open build.gradle for library project
Write two tasks in build.gradle -- deleteJar and createJar and add rule createJar.dependsOn(deleteJar, build)
The code from above:
task deleteJar(type: Delete) {
delete 'libs/jars/logmanagementlib.jar'
}
tas...