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How to hide output of subprocess in Python 2.7
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Redirect the output to DEVNULL:
import os
import subprocess
FNULL = open(os.devnull, 'w')
retcode = subprocess.call(['echo', 'foo'], stdout=FNULL, stderr=subprocess.STDOUT)
It is effectively the same as running this shell command:
retcode = os.system("echo 'fo...
What happens to a detached thread when main() exits?
..._local) variables of other threads nor static objects.
This appears to be allowed to allow thread managers as static objects (note in [basic.start.term]/4 says as much, thanks to @dyp for the pointer).
Problems arise when the destruction of static objects has finished, because then execution enter...
How to debug Lock wait timeout exceeded on MySQL?
In my production error logs I occasionally see:
11 Answers
11
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Generating random numbers in Objective-C
...te the S-Boxes via
arc4random_addrandom().
There is no need to call arc4random_stir() before using arc4random(), since arc4random() automatically
initializes itself.
EXAMPLES
The following produces a drop-in replacement for the traditional rand() and random() functions using
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Installation Issue with matplotlib Python [duplicate]
I have issue after installing the matplotlib package unable to import matplotlib.pyplot as plt . Any suggestion will be greatly appreciate.
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MySQL CONCAT returns NULL if any field contain NULL
...es: it returns the first non-NULL value parameter passed to it (or NULL if all parameters are NULL). By passing an empty string as the second parameter, you are guaranteeing it will not return NULL.
– Jo.
Mar 10 '17 at 17:03
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Random strings in Python
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In many cases, random isn't really required. Rather, all you really need is unique.
– Chase Seibert
Jan 8 '10 at 19:48
1
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pip broke. how to fix DistributionNotFound error?
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Works great on Mac OS X 10.9 as well. Thanks!
– Anton Babenko
Oct 23 '13 at 16:56
2
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Can't find the 'libpq-fe.h header when trying to install pg gem
...on Rails 3.1 pre version. I like to use PostgreSQL, but the problem is installing the pg gem. It gives me the following error:
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NSLog the method name with Objective-C in iPhone
...happens to be implemented as a C-string (as of the current versions of Mac OS X and the iPhone OS) doesn't mean you should use it in that way, since Apple could change it in an OS update.
– Nick Forge
May 5 '10 at 8:06
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