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How does push notification technology work on Android?
...emented their push notification feature? Does it work through polling done by a service running in the background or in a different way?
...
How do I remove code duplication between similar const and non-const member functions?
...on p. 23, in Item 3 "Use const whenever possible," in Effective C++, 3d ed by Scott Meyers, ISBN-13: 9780321334879.
Here's Meyers' solution (simplified):
struct C {
const char & get() const {
return c;
}
char & get() {
return const_cast<char &>(static_cast<cons...
UIPopovercontroller dealloc reached while popover is still visible
...en you don't need to keep a reference to the popover because it is managed by the presentation controller.
Code example (works both on iPhone and iPad):
UIImagePickerController *picker = [[UIImagePickerController alloc] init];
picker.delegate = self;
picker.sourceType = UIImagePickerControllerSour...
How can I lock a file using java (if possible)
... the lock of for the JVM, and not suitable for locking the file for access by individual threads within a single JVM.
– Stu Thompson
Sep 25 '08 at 7:00
11
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How can I check file size in Python?
...
You need the st_size property of the object returned by os.stat. You can get it by either using pathlib (Python 3.4+):
>>> from pathlib import Path
>>> Path('somefile.txt').stat()
os.stat_result(st_mode=33188, st_ino=6419862, st_dev=16777220, st_nlink=1, st_u...
How to find foreign key dependencies in SQL Server?
...samkitshah: Nobody said it would. The question is tagged sql-server, which by definition is Microsoft technology. Postgres has nothing to do with it.
– Neolisk
Jan 9 '15 at 20:27
2...
R script line numbers at error?
...l debugging suspects:
debug()
browser()
options(error=recover) [followed by options(error = NULL) to revert it]
You might want to look at this related post.
[Edit:] Sorry...just saw that you're running this from the command line. In that case I would suggest working with the options(error) fun...
Adding n hours to a date in Java?
...a.util.Calendar, and java.text.SimpleDateFormat are now legacy, supplanted by the java.time classes built into Java 8 & Java 9. See Tutorial by Oracle.
– Basil Bourque
Mar 25 '18 at 18:48
...
find: missing argument to -exec
...ated with a ; (so you usually need to type \; or ';' to avoid interpretion by the shell) or a +. The difference is that with ;, the command is called once per file, with +, it is called just as few times as possible (usually once, but there is a maximum length for a command line, so it might be spli...
Git Bash is extremely slow on Windows 7 x64
...
You can significantly speed up Git on Windows by running three commands to set some config options:
git config --global core.preloadindex true
git config --global core.fscache true
git config --global gc.auto 256
Notes:
core.preloadindex does filesystem operations i...