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C++0x has no semaphores? How to synchronize threads?
...ck Overflow regarding the use of semaphores. I use them (posix semaphores) all the time to let a thread wait for some event in another thread:
...
SecurityException: Permission denied (missing INTERNET permission?)
this error is really really really strange and I don't know how to reproduce it and how to fix it because I made a lot of searches but nothing was useful.
...
Reading large text files with streams in C#
...ock of bytes in memory used to cache data, thereby reducing the number of calls to the operating system. Buffers improve read and write performance. A buffer can be used for either reading or writing, but never both simultaneously. The Read and Write methods of BufferedStream automatically maintain ...
Fast way to get image dimensions (not filesize)
...r if it reads the whole data for that though. See the manpage of exiv2 for all supported image formats.
head -n1 will give you the dimensions for PPM, PGM formats.
For formats popular on the web, both exiv2 and identify will do the job.
Depending on the use-case you may need to write your own scri...
AtomicInteger lazySet vs. set
...l values for a while, but you'd
like to ensure that structures are eventually GCable. In such
cases, you can get better performance by avoiding
the costs of the null volatile-write. There are a few
other use cases along these lines for non-reference-based
atomics as well, so the method is ...
How to “pull” from a local branch into another one?
...ut. I made an experimental branch a while ago, and now I'd like to pull in all the changes that happened on master since I made it. This is all local. I want to pull from local master into local my_branch, but I can't do it. This doesn't seem to work, telling me that master isn't a git repository:
...
How to make a JSONP request from Javascript without JQuery?
...cument.createElement('script');
script.src = '//example.com/path/to/jsonp?callback=foo'
document.getElementsByTagName('head')[0].appendChild(script);
// or document.head.appendChild(script) in modern browsers
share
...
Generator Expressions vs. List Comprehension
...or slicing
print [5,6] + gen() # generators can't be added to lists
Basically, use a generator expression if all you're doing is iterating once. If you want to store and use the generated results, then you're probably better off with a list comprehension.
Since performance is the most common rea...
Standard concise way to copy a file in Java?
...
As toolkit mentions above, Apache Commons IO is the way to go, specifically FileUtils.copyFile(); it handles all the heavy lifting for you.
And as a postscript, note that recent versions of FileUtils (such as the 2.0.1 release) have added the use of NIO for copying files; NIO can significantly ...
How to modify existing, unpushed commit messages?
... the most recent commit message
git commit --amend
will open your editor, allowing you to change the commit message of the most recent commit. Additionally, you can set the commit message directly in the command line with:
git commit --amend -m "New commit message"
…however, this can make multi-...