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Purpose of Unions in C and C++
I have used unions earlier comfortably; today I was alarmed when I read this post and came to know that this code
15 Ans...
Multiprocessing - Pipe vs Queue
...ssed here
return args[0]['that']
except:
print "FATAL: reader({0}) exited while multiprocessing".format(args)
traceback.print_exc()
Now, when you find a crash you see something like:
FATAL: reader([{'crash': 'this'}]) exited while multiprocessing
Traceback (most recen...
What GRANT USAGE ON SCHEMA exactly do?
...Postgres database, so this is probably a stupid question. I assigned basic read-only permissions to the db role that must access the database from my php scripts, and I have a curiosity: if I execute
...
What does “atomic” mean in programming?
... and a second one which writes the last 32 bits. That means that another thread might read the value of foo, and see the intermediate state.
Making the operation atomic consists in using synchronization mechanisms in order to make sure that the operation is seen, from any other thread, as a single...
What does the comma operator , do?
...
I've seen used most in while loops:
string s;
while(read_string(s), s.len() > 5)
{
//do something
}
It will do the operation, then do a test based on a side-effect. The other way would be to do it like this:
string s;
read_string(s);
while(s.len() > 5)
{
//do so...
Handling warning for possible multiple enumeration of IEnumerable
...e semantic missing here is that a caller, who perhaps doesn't take time to read the details of the method, may assume you only iterate once - so they pass you an expensive object. Your method signature doesn't indicate either way.
By changing the method signature to IList/ICollection, you will at ...
How to write to file in Ruby?
I need to read the data out of database and then save it in a text file.
7 Answers
7
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Why is volatile not considered useful in multithreaded C or C++ programming?
...o be confused about the utility (or lack thereof) of volatile in multi-threaded programming contexts.
9 Answers
...
Set a default parameter value for a JavaScript function
...S6/ES2015, default parameters are in the language specification.
function read_file(file, delete_after = false) {
// Code
}
just works.
Reference: Default Parameters - MDN
Default function parameters allow formal parameters to be initialized with default values if no value or undefined is ...
What's the difference between a file descriptor and file pointer?
... systems.
You pass "naked" file descriptors to actual Unix calls, such as read(), write() and so on.
A FILE pointer is a C standard library-level construct, used to represent a file. The FILE wraps the file descriptor, and adds buffering and other features to make I/O easier.
You pass FILE pointe...