大约有 43,000 项符合查询结果（耗时：0.0486秒） [XML]
Recursive Lock (Mutex) vs Non-Recursive Lock (Mutex)
... to be recursive. That means the same thread can lock the same mutex twice and won't deadlock. Of course it also needs to unlock it twice, otherwise no other thread can obtain the mutex. Not all systems supporting pthreads also support recursive mutexes, but if they want to be POSIX conform, they h...
Is “IF” expensive?
...can't, for the life of me, remember what exactly our teacher said that day and I'm hoping you would probably know.
16 Answe...
Git commit with no commit message
...providing a meaningful commit message is part of good development practice and good repository stewardship. The first line of the commit message is used all over the place within git; for more, read "A Note About Git Commit Messages".
If you open Terminal.app, cd to your project directory, and git ...
Checkout old commit and make it a new commit [duplicate]
On Git, say I mess up my commits, and I want to make the version 3 commits ago as the new version. If I do git checkout xxxx , it creates a new branch and it seems like I can only merge it? Could I make this the new "master version"?
...
Get file size, image width and height before upload
How can I get the file size, image height and width before upload to my website, with jQuery or JavaScript?
7 Answers
...
How to prevent ifelse() from turning Date objects into numeric objects
... to manipulate a date vector. I expected the result to be of class Date , and was surprised to get a numeric vector instead. Here is an example:
...
What do I need to do to get Internet Explorer 8 to accept a self signed certificate?
...Options.
Select Security➞Trusted sites➞Sites.
Confirm the URL matches, and click “Add” then “Close”.
Close the “Internet Options” dialog box with either “OK” or “Cancel”.
Refresh the current page.
When told “There is a problem with this website's security certificate.”, c...
How do I specify different layouts for portrait and landscape orientations?
...to specify two separate layout xml files for an activity, one for Portrait and one for Landscape. I've not been to find any information on how to do that though. How do I specify for each activity which xml file is it's portrait layout and which is the Landscape layout?
...
How can I merge two commits into one if I already started rebase?
...base todo list, that is into a commit on a previous line. Changing the command on your todo list’s very first line to squash will always produce this error as there is nothing for the first commit to squash into.
The Fix
First get back to where you started with
$ git rebase --abort
Say your h...
Type erasure techniques
... erasure techniques in C++ are done with function pointers (for behaviour) and void* (for data). The "different" methods simply differ in the way they add semantic sugar. Virtual functions, e.g., are just semantic sugar for
struct Class {
struct vtable {
void (*dtor)(Class*);
vo...