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Proper stack and heap usage in C++?
I've been programming for a while but It's been mostly Java and C#. I've never actually had to manage memory on my own. I recently began programming in C++ and I'm a little confused as to when I should store things on the stack and when to store them on the heap.
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How to use hex color values
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How would you handle 123ABC? The compiler is burking at it not being a digit.
– Islam Q.
Mar 2 '16 at 6:28
1
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How can I distribute python programs?
... with disutils for Linux, and Py2exe or something similar for Windows. For OS X I don't know. If it's an end user application you would probably want an disk image type of thing, I don't know how to do that. But read this post for more information on the user experience of it. For an application mad...
Socket 错误返回码详解 - C/C++ - 清泛网 - 专注C/C++及内核技术
...imed out
Socket error 10061 - Connection refused
Socket error 10064 - Host is down
Socket error 10065 - No route to host
Socket error 10067 - Too many processes
Socket error 10091 - Network subsystem is unavailable
Socket error 10092 - WINSOCK.DLL version out of range
Socket error 1009...
Python concatenate text files
...if they were a single file is very handy. (Also, the fact that fileinput closes each file as soon as it's done means there's no need to with or close each one, but that's just a one-line savings, not that big of a deal.)
There are some other nifty features in fileinput, like the ability to do in-pl...
Visibility of global variables in imported modules
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Globals in Python are global to a module, not across all modules. (Many people are confused by this, because in, say, C, a global is the same across all implementation files unless you explicitly make it static.)
There are different ways to solve this, depending on your ac...
setuptools: package data folder location
...unction to __init__.py to locate an absolute path to a data
file:
import os
_ROOT = os.path.abspath(os.path.dirname(__file__))
def get_data(path):
return os.path.join(_ROOT, 'data', path)
print get_data('resource1/foo.txt')
Outputs:
/Users/pat/project/foo/data/resource1/foo.txt
After th...
Understanding :source option of has_one/has_many through of Rails
...'ve chosen to namespace the Dog::Breed, because we want to access Dog.find(123).breeds as a nice and convenient association.
Now, if we now want to create a has_many :dog_breeds, :through => :dogs association on Pet, we suddenly have a problem. Rails won't be able to find a :dog_breeds associati...
'^M' character at end of lines
...the SQL script as it is echoed to the command-line. I don't know on which OS the SQL script was originally created.
16 Ans...
How do I create a unique constraint that also allows nulls?
...et_AllowNull
UNIQUE (TicketID, TicketUnique);
If IssueID 1 has ticket 123, the UNIQUE constraint will be on values (123, NULL). If IssueID 2 has no ticket, it will be on (NULL, 2). Some thought will show that this constraint cannot be duplicated for any row in the table, and still allows multip...