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What is the difference between sigaction and signal?
I was about to add an extra signal handler to an app we have here and I noticed that the author had used sigaction() to set up the other signal handlers. I was going to use signal() . To follow convention I should use sigaction() but if I was writing from scratch, which should I choose?
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How to read the content of a file to a string in C?
...least lines of code, however you want to interpret it) to open a file in C and read its contents into a string (char*, char[], whatever)?
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MySQL SELECT WHERE datetime matches day (and not necessarily time)
...ults when using BETWEEN with date or time values, use CAST() to explicitly convert the values to the desired data type. Examples: If you compare a DATETIME to two DATE values, convert the DATE values to DATETIME values. If you use a string constant such as '2001-1-1' in a comparison to a DATE, cast ...
Transpose/Unzip Function (inverse of zip)?
I have a list of 2-item tuples and I'd like to convert them to 2 lists where the first contains the first item in each tuple and the second list holds the second item.
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TypeError: 'dict_keys' object does not support indexing
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Convert an iterable to a list may have a cost. Instead, to get the the first item, you can use:
next(iter(keys))
Or, if you want to iterate over all items, you can use:
items = iter(keys)
while True:
try:
item...
Start thread with member function
...o construct a std::thread with a member function that takes no arguments and returns void . I can't figure out any syntax that works - the compiler complains no matter what. What is the correct way to implement spawn() so that it returns a std::thread that executes test() ?
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Properly escape a double quote in CSV
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I know this is an old post, but here's how I solved it (along with converting null values to empty string) in C# using an extension method.
Create a static class with something like the following:
/// <summary>
/// Wraps value in quotes if necessary and converts nulls to empt...
Best way to repeat a character in C#
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string.Concat(Enumerable.Repeat("ab", 2));
Returns
"abab"
And
string.Concat(Enumerable.Repeat("a", 2));
Returns
"aa"
from...
Is there a built-in function to repeat string or char in .net?
share
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Why malloc+memset is slower than calloc?
...se it can skip memset() entirely. In other cases, calloc() can even cheat and not allocate any memory! However, malloc()+memset() will always do the full amount of work.
Understanding this requires a short tour of the memory system.
Quick tour of memory
There are four main parts here: your prog...
How to change the default collation of a table?
...set and collation of a table including those of existing columns (note the convert to clause):
alter table <some_table> convert to character set utf8mb4 collate utf8mb4_unicode_ci;
Edited the answer, thanks to the prompting of some comments:
Should avoid recommending utf8. It's almost n...