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How to create a file with a given size in Linux?
...a huge blocksize will perform much worse once it gets very big, as it will allocate and read that amount into memory before writing. If this is somethig like bs=4GiB you'll probably end up swapping.
– Brian
Sep 29 '08 at 7:40
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What is Pseudo TTY-Allocation? (SSH and Github)
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As explained in "gitolite: PTY allocation request failed on channel 0", it is important to do ssh test connection with -T, because some server could abort the transaction entirely if a text-terminal (tty) is requested.
-T avoids requesting said terminal, ...
UIPopovercontroller dealloc reached while popover is still visible
...ne and iPad):
UIImagePickerController *picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
picker.sourceType = UIImagePickerControllerSourceTypeCamera;
picker.allowsEditing = YES;
picker.modalPresentationStyle = UIModalPresentationPopover;
UIPopoverPresentationController* popov...
Setting direction for UISwipeGestureRecognizer
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UISwipeGestureRecognizer *swipeLeftRight = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleGesture:)];
[swipeLeftRight setDirection:(UISwipeGestureRecognizerDirectionRight | UISwipeGestureRecognizerDirectionLeft )];
[self.view addGestureRecognizer:swipeLeftR...
Why is whitespace sometimes needed around metacharacters?
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There is a list of characters that separate tokens in BASH. These characters are called metacharacters and they are |, &, ;, (, ), <, >, space and tab. On the other hand, curly braces ({ and }) are just ordinary characters that make up words.
Omitting the se...
When is a C++ destructor called?
...with another object of the same type but don't want to free memory just to allocate it again. You can destroy the old object in place and construct a new one in place. (However, generally this is a bad idea.)
// pointer is destroyed because it goes out of scope,
// but not the object it pointed to....
How to display a dynamically allocated array in the Visual Studio debugger?
If you have a statically allocated array, the Visual Studio debugger can easily display all of the array elements. However, if you have an array allocated dynamically and pointed to by a pointer, it will only display the first element of the array when you click the + to expand it. Is there an eas...
Why is creating a Thread said to be expensive?
... there is a fair bit of work involved:
A large block of memory has to be allocated and initialized for the thread stack.
System calls need to be made to create / register the native thread with the host OS.
Descriptors need to be created, initialized and added to JVM-internal data structures.
It...
How to add a button to UINavigationBar?
...tton on a NavigationBar.
UIBarButtonItem *rightButton = [[UIBarButtonItem alloc] initWithTitle:@"Done"
style:UIBarButtonItemStyleDone target:nil action:nil];
UINavigationItem *item = [[UINavigationItem alloc] initWithTitle:@"Title"];
item.rightBarButtonItem = rightButton;
item.hidesBackButton ...
Allow CORS REST request to a Express/Node.js application on Heroku
...problem and the solution was not related to CORS.
Turns out that JSON Web Token secret string was not defined in the environment variables, so the token could not be signed.
This caused to any POST request that relies on checking or signing a token to get a timeout and return a 503 error, telling t...