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How to urlencode data for curl command?
I am trying to write a bash script for testing that takes a parameter and sends it through curl to web site. I need to url encode the value to make sure that special characters are processed properly. What is the best way to do this?
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The Definitive C++ Book Guide and List
...purely as a reference for experienced users willing to devote considerable time and effort to its understanding. The C++17 standard is released in electronic form for 198 Swiss Francs.
The C++17 standard is available, but seemingly not in an economical form – directly from the ISO it costs 198 Sw...
PHP abstract properties
..., there is no way to enforce that with the compiler, you'd have to use run-time checks (say, in the constructor) for the $tablename variable, e.g.:
class Foo_Abstract {
public final function __construct(/*whatever*/) {
if(!isset($this->tablename))
throw new LogicException(get_class($...
What does “SyntaxError: Missing parentheses in call to 'print'” mean in Python?
...o!")?
Since the "Missing parentheses in call to print" case is a compile time syntax error and hence has access to the raw source code, it's able to include the full text on the rest of the line in the suggested replacement. However, it doesn't currently try to work out the appropriate quotes to p...
Do htmlspecialchars and mysql_real_escape_string keep my PHP code safe from injection?
...a wrapper like PEAR DB
Make sure that magic_quotes_gpc and magic_quotes_runtime are off at all times, and never get accidentally turned on, not even briefly. These are an early and deeply misguided attempt by PHP's developers to prevent security problems (which destroys data)
There isn't really a ...
DESTDIR and PREFIX of make
...Sepcify a different --prefix location/option for each build - at configure time. For eg:
untar petsc tar ball
./configure --prefix=/opt/petsc/petsc-3.9.0-mpich --with-mpi-dir=/opt/mpich
make
make install DESTDIR=/tmp/petsc-pkg
untar petsc tar ball
./configure --prefix=/opt/petsc/petsc-3.9.0-openmpi...
How to forward declare a C++ template class?
...e a templated class whose definition states the default arguments, but any time you reference the class you must include all of its arguments until the definition is introduced.
eg. Let's use std::vector without including it (the second argument of std::vector is defined with a default):
namespace s...
Haskell: Lists, Arrays, Vectors, Sequences
...
The first problem with lists is that to index into them (!!) takes ϴ(k) time, which is annoying. Also, appends can be slow ++, but Haskell's lazy evaluation model means that these can be treated as fully amortized, if they happen at all.
The second problem with lists is that they have poor data ...
What are copy elision and return value optimization?
... to a temp, and copy 2 from temp to obj; 2nd is when one of the above is optimezed, probably the reutnr copy is elided; the thris both are elided
– victor
Nov 7 '14 at 16:06
3
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What is the main difference between Inheritance and Polymorphism?
...entation of read, which method gets called is determined for you by the runtime, depending if you have a Person or a Student. It gets a bit tricky, but if you do something like
Person p = new Student();
p.read();
the read method on Student gets called. Thats the polymorphism in action. You can...