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What are the differences between poll and select?
I am referring to the POSIX standard select and poll system C API calls.
3 Answers
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In Matlab, when is it optimal to use bsxfun?
...t of good answers to Matlab questions on SO frequently use the function bsxfun . Why?
5 Answers
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Do I encode ampersands in ?
...L recommendations, the ampersand must be escaped e.g. as & in contexts like this. However, browsers do not require it, and the HTML5 CR proposes to make this a rule, so that special rules apply in attribute values. Current HTML5 validators are outdated in this respect (see bug report with co...
Sleep until a specific time/date
...n to nanoseconds (effectively more around milliseconds) use e.g. this syntax:
current_epoch=$(date +%s.%N)
target_epoch=$(date -d "20:25:00.12345" +%s.%N)
sleep_seconds=$(echo "$target_epoch - $current_epoch"|bc)
sleep $sleep_seconds
Note that macOS / OS X does not support precision below secon...
Why not use java.util.logging?
...till not convinced, JB Nizet makes an additional and potent argument:
Except the end user could have already done this customization for his
own code, or another library that uses log4j or logback. j.u.l is
extensible, but having to extend logback, j.u.l, log4j and God only
knows which oth...
Rich vs Anemic Domain Model [closed]
...use a Rich Domain Model over an Anemic Domain Model, and looking for good examples of the two.
10 Answers
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Why should casting be avoided? [closed]
...es (more or less) a fourth answer.
Since it's the one you didn't mention explicitly, I'll start with C. C casts have a number of problems. One is that they can do any of a number of different things. In some cases, the cast does nothing more than tell the compiler (in essence): "shut up, I know wha...
Can I 'git commit' a file and ignore its content changes?
...
Sure, I do exactly this from time to time using
git update-index --assume-unchanged [<file> ...]
To undo and start tracking again (if you forgot what files were untracked, see this question):
git update-index --no-assume-unchanged...
__lt__ instead of __cmp__
Python 2.x has two ways to overload comparison operators, __cmp__ or the "rich comparison operators" such as __lt__ . The rich comparison overloads are said to be preferred, but why is this so?
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Is there any advantage of using map over unordered_map in case of trivial keys?
... and if you can't afford them, then you can't use it.
Just from personal experience, I found an enormous improvement in performance (measured, of course) when using unordered_map instead of map in a main entity look-up table.
On the other hand, I found it was much slower at repeatedly inserting an...