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Reading a binary file with python
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See this answer if you need to convert an unpacked char[] to a string.
– PeterM
May 20 '16 at 14:57
...
When should you not use virtual destructors?
...ays that if you were to copy from an object with POD type into an array of chars (or unsigned chars) and back again, then the result will be the same as the original object.]
Modern C++
In recent versions of C++, the concept of POD was split between the class layout and its construction, copying a...
Why should I declare a virtual destructor for an abstract class in C++?
...
{
public:
virtual void DoFoo() = 0;
};
class Bar : public IFoo
{
char* dooby = NULL;
public:
virtual void DoFoo() { dooby = new char[10]; }
void ~Bar() { delete [] dooby; }
};
IFoo* baz = new Bar();
baz->DoFoo();
delete baz; // memory leak - dooby isn't deleted
...
Missing Push Notification Entitlement
...from the answer given by @Vaiden, in Xcode 8 you can resolve this issue by selecting the target and clicking the "Fix issue". Of course, you'll still need to set up push notifications in the Apple Developer portal (you can simplify the process a little by using the new "Automatically manage signing"...
Sequence contains no elements?
...in dc.BlogPosts
where p.BlogPostID == id
select p).Single();
Also; if this is LINQ-to-SQL, then in the current version you get a slightly better behaviour if you use the form:
var id = ID;
BlogPost post = dc.BlogPosts.Single(p => p.BlogPostID == id);
...
PostgreSQL Autoincrement
...RT INTO foo (bar) values ('blah');
INSERT INTO foo (bar) values ('blah');
SELECT * FROM foo;
1,blah
2,blah
SERIAL is just a create table time macro around sequences. You can not alter SERIAL onto an existing column.
sha...
PostgreSQL: insert from another table
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Just supply literal values in the SELECT:
INSERT INTO TABLE1 (id, col_1, col_2, col_3)
SELECT id, 'data1', 'data2', 'data3'
FROM TABLE2
WHERE col_a = 'something';
A select list can contain any value expression:
But the expressions in the select list do...
What does SQL clause “GROUP BY 1” mean?
...
SELECT account_id, open_emp_id
^^^^ ^^^^
1 2
FROM account
GROUP BY 1;
In above query GROUP BY 1 refers to the first column in select statement which is
account_id.
You also can speci...
Get the Highlighted/Selected text
...
Getting the text the user has selected is relatively simple. There's no benefit to be gained by involving jQuery since you need nothing other than the window and document objects.
function getSelectionText() {
var text = "";
if (window.getSelecti...
Xcode 6 - How to pick signing certificate/provisioning profile for Ad-Hoc distribution?
...ple.com and find the distribution provisioning profile you want to use.
2) Select it, click "Edit", re-name the profile, and click "Generate".
3) Download the provisioning profile to the Desktop and drag it onto the Xcode 6 icon.
4) Re-start Xcode 6.
5) Open the organizer window and click "Submit" o...