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Ruby sleep or delay less than a second?
... per second, but I need to wait 1/24th of a second between sending the commands. What is the best way to sleep for less than a second?
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How to use Bash to create a folder if it doesn't already exist?
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First, in bash "[" is just a command, which expects string "]" as a last argument, so the whitespace before the closing bracket (as well as between "!" and "-d" which need to be two separate arguments too) is important:
if [ ! -d /home/mlzboy/b2c2/shared/db...
What are the differences between utf8_general_ci and utf8_unicode_ci? [duplicate]
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utf8_general_ci is a very simple — and on Unicode, very broken — collation, one that gives incorrect results on general Unicode text. What it does is:
converts to Unicode normalization form D for canonical decomposition
removes any combining characters
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How can I programmatically check whether a keyboard is present in iOS app?
...take the easy way:
When you enter a textField, it becomes first responder and the keyboard appears.
You can check the status of the keyboard with [myTextField isFirstResponder]. If it returns YES, then the the keyboard is active.
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How do I change read/write mode for a file using Emacs?
If a file is set to read only mode, how do I change it to write mode and vice versa from within Emacs?
9 Answers
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How do I check that a Java String is not all whitespaces?
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@Andreas_D: Heh, I got my orders! The OP said he wanted to check a string or char array, he never said anything about nulls! :) *checks the fine print in the contract* "null is not a string!"
– Carl Smotr...
What does “S3 methods” mean in R?
Since I am fairly new to R, I do not know what the S3 methods and objects are. I found that there are S3 and S4 object systems, and some recommend to use S3 over S4 if possible (See Google's R Style Guide at http://google-styleguide.googlecode.com/svn/trunk/google-r-style.html )*. However, I do not...
Meaning of 'const' last in a function declaration of a class?
...method the this pointer will essentially become a pointer to const object, and you cannot therefore change any member data. (Unless you use mutable, more on that later).
The const keyword is part of the functions signature which means that you can implement two similar methods, one which is called ...
How to make a copy of a file in android?
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To copy a file and save it to your destination path you can use the method below.
public static void copy(File src, File dst) throws IOException {
InputStream in = new FileInputStream(src);
try {
OutputStream out = new File...
Add new column with foreign key constraint in one command
... new column that will be a foreign key. I have been able to add the column and the foreign key constraint using two separate ALTER TABLE commands:
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