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What do the f and t commands do in Vim?
... information but people keep telling me that they are very useful. Would really appreciate an answer with an example if possible, thanks!
...
Are parallel calls to send/recv on the same socket valid?
...tions, so assuming you're talking about POSIX send/recv then yes, you can call them simultaneously from multiple threads and things will work.
This doesn't necessarily mean that they'll be executed in parallel -- in the case of multiple sends, the second will likely block until the first completes....
Run java jar file on a server as background process
...on
[Service]
ExecStart=/usr/bin/java -jar /web/server.jar
User=user
[Install]
WantedBy=multi-user.target
Step 4:
Run your service
as super user
$ systemctl start whatever_you_want.service # starts the service
$ systemctl enable whatever_you_want.service # auto starts the service
$ systemctl ...
Abstract class in Java
...h the inheriting subclass must implement.
Provide a common interface which allows the subclass to be interchanged with all other subclasses.
Here's an example:
abstract public class AbstractClass
{
abstract public void abstractMethod();
public void implementedMethod() { System.out.print("...
List all files and directories in a directory + subdirectories
...
string[] allfiles = Directory.GetFiles("path/to/dir", "*.*", SearchOption.AllDirectories);
where *.* is pattern to match files
If the Directory is also needed you can go like this:
foreach (var file in allfiles){
FileInfo in...
Suppress deprecated import warning in Java
...ate source of truth is javac for which the fix doesn't work. This answer really answers the question: stackoverflow.com/a/20909204/2032701
– Ruslan
Sep 26 '17 at 14:12
...
What does the star operator mean, in a function call?
...ues = (1, 2)
s = sum(*values)
This will unpack the tuple so that it actually executes as:
s = sum(1, 2)
The double star ** does the same, only using a dictionary and thus named arguments:
values = { 'a': 1, 'b': 2 }
s = sum(**values)
You can also combine:
def sum(a, b, c, d):
return a ...
Cannot change column used in a foreign key constraint
...eign key field and reference must be equal.
This means your foreign key disallows changing the type of your field.
One solution would be this:
LOCK TABLES
favorite_food WRITE,
person WRITE;
ALTER TABLE favorite_food
DROP FOREIGN KEY fk_fav_food_person_id,
MODIFY person_id SMALLIN...
Troubleshooting “The use statement with non-compound name … has no effect”
...
PHP's use isn't the same as C++'s using namespace; it allows you to define an alias, not to "import" a namespace and thus henceforth omit the namespace qualifier altogether.
So, you could do:
use Blog\Article as BA;
... to shorten it, but you cannot get rid of it entirely.
...
Why is the use of alloca() not considered good practice?
alloca() allocates memory on the stack rather than on the heap, as in the case of malloc() . So, when I return from the routine the memory is freed. So, actually this solves my problem of freeing up dynamically allocated memory. Freeing of memory allocated through malloc() is a major headache an...