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Detecting endianness programmatically in a C++ program
...punning - it will often be warned against by compiler. That's exactly what unions are for !
bool is_big_endian(void)
{
union {
uint32_t i;
char c[4];
} bint = {0x01020304};
return bint.c[0] == 1;
}
The principle is equivalent to the type case as suggested by others, ...
Selecting only first-level elements in jquery
How can I select the link elements of only the parent <ul> from a list like this?
10 Answers
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How do I print a double value with full precision using cout?
...int out the binary bits (or hex nybbles).
One way of doing that is using a union to type-pun the double to a integer and then printing the integer, since integers do not suffer from truncation or round-off issues. (Type punning like this is not supported by the C++ standard, but it is supported in C...
Making macOS Installer Packages which are Developer ID ready
...gbuild
persisting obsolescence
Known Issues and Workarounds
Destination Select Pane
The user is presented with the destination select option with only a single choice - "Install for all users of this computer". The option appears visually selected, but the user needs to click on it in order to p...
IIS - 401.3 - Unauthorized
... configuration of your site, modify the "Anonymous authentication" line by selecting "Identity of the application pool" instead of "Specific user".
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Fetch the row which has the Max value for a column
... multiple rows for the userid where the maximum date is on multiple rows.
select userid,
my_date,
...
from
(
select userid,
my_date,
...
max(my_date) over (partition by userid) max_my_date
from users
)
where my_date = max_my_date
"Analytic functions rock"
Edi...
SQL - find records from one table which don't exist in another
...shortest statement, and may be quickest if your phone book is very short:
SELECT *
FROM Call
WHERE phone_number NOT IN (SELECT phone_number FROM Phone_book)
alternatively (thanks to Alterlife)
SELECT *
FROM Call
WHERE NOT EXISTS
(SELECT *
FROM Phone_book
WHERE Phone_book.phon...
Oracle: If Table Exists
...
declare
c int;
begin
select count(*) into c from user_tables where table_name = upper('table_name');
if c = 1 then
execute immediate 'drop table table_name';
end if;
end;
That's for checking whether a table in the current schema exi...
How to make rpm auto install dependencies
...
thanks, I was struggling to install mysql-workbench with rpm -ivh. eventually ended up with this post. DNF did the trick.
– BlueBird
Jul 13 '16 at 13:10
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What is the difference between HashSet and List?
...ady existing in Set
Can perform mathematical set operations against a Set: Union/Intersection/IsSubsetOf etc.
HashSet doesn't implement IList only ICollection
You cannot use indices with a HashSet, only enumerators.
The main reason to use a HashSet would be if you are interested in performing Set ...