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In the shell, what does “ 2>&1 ” mean?
...iptor 1 is the standard output (stdout).
File descriptor 2 is the standard error (stderr).
Here is one way to remember this construct (although it is not entirely accurate): at first, 2>1 may look like a good way to redirect stderr to stdout. However, it will actually be interpreted as "redirect...
Have bash script answer interactive prompts [duplicate]
Is it possible to have a bash script automatically handle prompts that would normally be presented to the user with default actions? Currently I am using a bash script to call an in-house tool that will display prompts to the user (prompting for Y/N) to complete actions, however the script I'm writ...
Does SQLAlchemy have an equivalent of Django's get_or_create?
... Look at Django's implementation of get_or_create. It checks for integrity error, and relies upon proper use of unique constraints.
– Ivan Virabyan
May 21 '12 at 6:17
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How do you run a single test/spec file in RSpec?
I want to be able to run a single spec file's tests — for the one file I'm editing, for example. rake spec executes all the specs. My project is not a Rails project, so rake spec:doc doesn't work.
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How do I encode/decode HTML entities in Ruby?
I am trying to decode some HTML entities, such as '&amp;lt;' becoming '<' .
7 Answers
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EF Migrations: Rollback last applied migration?
This looks like a really common task, but I can't find an easy way to do it.
14 Answers
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How to detect if a stored procedure already exists
I have to write a deployment script which will work if a stored procedure exists or does not exist. i.e. if it exists, then I need to alter it, otherwise create it.
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Remove empty strings from a list of strings
I want to remove all empty strings from a list of strings in python.
12 Answers
12
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Tools for Generating Mock Data? [closed]
...ption). Moreover going for one of the demos (hsqldb) with maven results in errors as well. To me it seems like the tool not in a good shape, thus not worth loosing the time with it.
– Peter Butkovic
Nov 7 '13 at 9:11
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What is the difference between quiet NaN and signaling NaN?
...e exit status:
g++ -ggdb3 -O0 -Wall -Wextra -pthread -std=c++11 -pedantic-errors -o blow_up.out blow_up.cpp -lm -lrt
./blow_up.out
echo $?
Output:
FE_ALL_EXCEPT snan + 1.0f
feenableexcept qnan + 1.0f
Floating point exception (core dumped)
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Note that this behaviour only happens with -O0 in G...