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Timer function to provide time in nano seconds using C++
...SD
clock_gettime(CLOCK_REALTIME, &ts); // Works on Linux
}
For windows you want to use the QueryPerformanceCounter. And here is more on QPC
Apparently there is a known issue with QPC on some chipsets, so you may want to make sure you do not have those chipset. Additionally some dual core A...
Disable password authentication for SSH [closed]
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How do I add new keys to the server, while password authentication is disabled? Surely there is a way to do this, without having to turn password authentication on, every time someone want's to add a key...
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How can I get the button that caused the submit from the form submit event?
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I leveraged document.activeElement as sketched in this answer: How to get the focused element with jQuery?
$form.on('submit', function() {
var $btn = $(document.activeElement);
if (
/* there is an activeElement at all *...
Drop shadow for PNG image in CSS
...he party, but yes, it is totally possible to create "true" dynamic drop shadows around alpha masked PNGs, using a combination of dropshadow-filter (for Webkit), SVG (for Firefox) and DX filters for IE.
.shadowed {
-webkit-filter: drop-shadow(12px 12px 25px rgba(0,0,0,0.5));
filter: url(#dro...
How to compare two strings in dot separated version format in Bash?
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Here is a pure Bash version that doesn't require any external utilities:
#!/bin/bash
vercomp () {
if [[ $1 == $2 ]]
then
return 0
fi
local IFS=.
local i ver1=($1) ver2=($2)
# fill empty fields in ver1 with zeros
for ((i=$...
Detect if device is iOS
...ction
|| (navigator.userAgent.includes("Mac") && "ontouchend" in document)
}
iOS will be either true or false
Worse option: User agent sniffing
User Agent sniffing is more dangerous and problems appear often.
On iPad iOS 13, the user agent is identical with that of a MacOS 13 computer, bu...
How can you find the height of text on an HTML canvas?
...ind a way to find out how tall it is. I know it's based on the font, but I don't know to convert a font string to a text height.
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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
...ional mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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SqlDataAdapter vs SqlDataReader
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SqlDataReader:
Holds the connection open until you are finished (don't forget to close it!).
Can typically only be iterated over once
Is not as useful for updating back to the database
On the other hand, it:
Only has one record in memory at a time rather than an entire result set (this c...
sql query to return differences between two tables
...ant to show all the discrepancies. I need to check three pieces of data in doing so, FirstName, LastName and Product.
12 An...