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Is errno thread-safe?
...t errno; so my question is, is it safe to check errno value after some calls or use perror() in multi-threaded code. Is this a thread safe variable? If not, then whats the alternative ?
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Can “using” with more than one resource cause a resource leak?
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No.
The compiler will generate a separate finally block for each variable.
The spec (§8.13) says:
When a resource-acquisition takes the form of a
local-variable-declaration, it is possible to acquire multiple
resources of a given type. A using statement of the...
What's the difference between using CGFloat and float?
I tend to use CGFloat all over the place, but I wonder if I get a senseless "performance hit" with this. CGFloat seems to be something "heavier" than float, right? At which points should I use CGFloat, and what makes really the difference?
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How do I raise the same Exception with a custom message in Python?
...ssign a special meaning to the elements of this tuple, while others are usually called only with a single string giving an error message.". So the code won't work arg[0] is not an error message (it could be an int, or it could be a string representing a file name).
– Trent
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How to use permission_required decorators on django class-based views
...ing how the new CBVs work. My question is this, I need to require login in all the views, and in some of them, specific permissions. In function-based views I do that with @permission_required() and the login_required attribute in the view, but I don't know how to do this on the new views. Is there ...
Python memoising/deferred lookup property decorator
...nce, but they're a real bottleneck to calculate that first time and only really accessed for special cases. Hence they can also be cached after they've been retrieved from the database (this therefore fits the definition of memoisation where the input is simply "no input").
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How do I create an HTML table with a fixed/frozen left column and a scrollable body?
... i also used jQuery to .clone() the table, once it has been generated by php+MySQL+ajax, and insert it into a cleaned out div...
– Peter
Mar 6 '18 at 22:27
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What do linkers do?
...converts the source file into object byte code. This byte code (sometimes called object code) is mnemonic instructions that only your computer architecture understands. Traditionally, these files have an .OBJ extension.
After the object file is created, the linker comes into play. More often than ...
Python, remove all non-alphabet chars from string
... Hmm, I can quite track it down, but what about the pattern to remove all non-alphanumerics excluding spaces?
– KDecker
Mar 20 '14 at 0:45
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How can i query for null values in entity framework?
...g this bug!
For backwards compatibility, it will be opt-in - you need manually enable a setting to make entry == value work. No word yet on what this setting is. Stay tuned!
Edit 2: According to this post by the EF team, this issue has been fixed in EF6! Woohoo!
We changed the default be...