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Waiting until two async blocks are executed before starting another block
...y Programming Guide
Your example could look something like this:
dispatch_group_t group = dispatch_group_create();
dispatch_group_async(group,dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), ^ {
// block1
NSLog(@"Block1");
[NSThread sleepForTimeInterval:5.0];
NSLog(@"Bl...
How to record webcam and audio using webRTC and a server-based Peer connection
...mediaOptions.audio;
navigator.mediaDevices.getUserMedia(media.gUM).then(_stream => {
stream = _stream;
id('gUMArea').style.display = 'none';
id('btns').style.display = 'inherit';
start.removeAttribute('disabled');
recorder = new MediaRecorder(stream);
recorder.ond...
Why hasn't functional programming taken over yet?
... answered May 14 '10 at 16:34
G__G__
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Export and Import all MySQL databases at one time
...zgür from the mysqldump man page: "mysqldump does not dump the INFORMATION_SCHEMA or performance_schema database by default. To dump either of these, name it explicitly on the command line and also use the --skip-lock-tables option."
– mmalone
Sep 23 '15 at 23...
How to ignore certain files in Git
...res just files that weren't tracked before (by git add). Run git reset name_of_file to unstage the file and keep it. In case you want to also remove the given file from the repository (after pushing), use git rm --cached name_of_file.
...
How to dismiss keyboard for UITextView with return key?
...n Xcode 6.4 , Swift 2.0. I set the key using IB.
– MB_iOSDeveloper
Jul 9 '15 at 7:20
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What is the difference between `sorted(list)` vs `list.sort()`?
...ably faster as it is written in C:
def sorted(iterable, key=None):
new_list = list(iterable) # make a new list
new_list.sort(key=key) # sort it
return new_list # return it
when to use which?
Use list.sort when you do not wish to retain the original sort ord...
Can not connect to local PostgreSQL
... the permissions on the socket file and its directories /var and /var/pgsql_socket. Your Rails app (OSX user) must have execute (x) permissions on these directories (preferably grant everyone permissions) and the socket should have full permissions (wrx). You can use ls -lAd <file> to check t...
Signed to unsigned conversion in C - is it always safe?
...hort Answer
Your i will be converted to an unsigned integer by adding UINT_MAX + 1, then the addition will be carried out with the unsigned values, resulting in a large result (depending on the values of u and i).
Long Answer
According to the C99 Standard:
6.3.1.8 Usual arithmetic conversions...
Which way is best for creating an object in JavaScript? Is `var` necessary before an object property
...
HEy @Alex_Nabu - I have already shared the examples in my post. If you still face any challenges please update me I will help you.
– Anand Deep Singh
Jun 21 '15 at 17:56
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