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What should I set JAVA_HOME environment variable on macOS X 10.6?
...a_home)
I haven't experienced any problems with that technique.
Occasionally I do have to change the value of JAVA_HOME to an earlier version of Java. For example, one program I'm maintaining requires 32-bit Java 5 on OS X, so when using that program, I set JAVA_HOME by running:
export JAVA_HOM...
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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How to capture stdout output from a Python function call?
...object.
This tool adds flexibility to existing functions or classes whose
output is hardwired to stdout.
For example, the output of help() normally is sent to sys.stdout. You
can capture that output in a string by redirecting the output to an
io.StringIO object:
f = io.StringIO() ...
Bash command to sum a column of numbers [duplicate]
...mn of numbers. I just want a quick one liner that will do something essentially like this:
10 Answers
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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...
How do I get my Python program to sleep for 50 milliseconds?
...rity, CPU load avg, available memory, and a plethora of other factors make all calls imprecise. The busier the system is, the higher the imprecision.
– David
Jan 28 '19 at 18:44
2...
How to fix java.net.SocketException: Broken pipe?
I am using apache commons http client to call url using post method to post the parameters and it is throwing the below error rarely.
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Random strings in Python
...
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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Using the Android Application class to persist data
..., the Application class does not have the same life-cycle (i.e. it is, for all intents and purposes, always instantiated). Does it make sense to store the state information inside of the application class and then reference it from the Activity, or is that generally not the "acceptable" method due ...
How do I get the directory that a program is running from?
... When I see code that looks at /proc part of me dies a little. All the world is not Linux, and even on that one platform /proc should be considered subject to change from version to version, arch to arch, etc.
– asveikau
Jan 28 '10 at 0:29
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