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What is the difference between C, C99, ANSI C and GNU C?
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Everything before standardization is generally called "K&R C", after the famous book, with Dennis Ritchie, the inventor of the C language, as one of the authors. This was "the C language" from 1972-1989.
The first C standard was released 1989 nationally in USA, ...
Entity Framework: There is already an open DataReader associated with this Command
I am using Entity Framework and occasionally i will get this error.
17 Answers
17
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Hidden features of Ruby
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From Ruby 1.9 Proc#=== is an alias to Proc#call, which means Proc objects can be used in case statements like so:
def multiple_of(factor)
Proc.new{|product| product.modulo(factor).zero?}
end
case number
when multiple_of(3)
puts "Multiple of 3"
when multiple...
How can one print a size_t variable portably using the printf family?
...on is to cast your variables to unsigned long long and use %llu to be maximally portable.
– Adam Rosenfield
Apr 13 '10 at 1:52
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Determine device (iPhone, iPod Touch) with iOS
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@AnilSivadas: UI_USER_INTERFACE_IDIOM() is safe to use in apps that still support iOS < 3.2: it is a macro in UIDevice.h specifically written to default to UIUserInterfaceIdiomPhone on such older iOS versions.
– mkle...
E11000 duplicate key error index in mongodb mongoose
... null value.
In other words, a sparse index is ok with multiple documents all having null values.
sparse indexes
From comments:
Your error says that the key is named mydb.users.$email_1 which makes me suspect that you have an index on both users.email and users.local.email (The former being old an...
How to ssh to vagrant without actually running “vagrant ssh”?
...sh" because it's -c option didn't pass on arguments properly. This is basically what it does (there might be more, but it works fine this way)
#!/bin/sh
PORT=$(vagrant ssh-config | grep Port | grep -o '[0-9]\+')
ssh -q \
-o UserKnownHostsFile=/dev/null \
-o StrictHostKeyChecking=no \
-i...
Android Facebook integration with invalid key hash
...eason. I have also got the same problem. So I tried it through programmatically.
Follow these steps:
Paste the following code in oncreate().
try {
PackageInfo info = getPackageManager().getPackageInfo(
"com.example.packagename",
PackageMan...
Is Dvorak typing appropriate for programming? [closed]
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There are Dvorak layouts specifically for programming: http://www.kaufmann.no/roland/dvorak/
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What is the dual table in Oracle?
...of dummy table with a single record used for selecting when you're not actually interested in the data, but instead want the results of some system function in a select statement:
e.g. select sysdate from dual;
See http://www.adp-gmbh.ch/ora/misc/dual.html
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