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What is the $? (dollar question mark) variable in shell scripting? [duplicate]
...al Parameters" http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_05_02 :
? Expands to the decimal exit status of the most recent pipeline (see Pipelines).
man bash "Special Parameters":
The shell treats several parameters specially. These parameters may only be refe...
Django: Why do some model fields clash with each other?
...
You have two foreign keys to User. Django automatically creates a reverse relation from User back to GameClaim, which is usually gameclaim_set. However, because you have two FKs, you would have two gameclaim_set attributes, which is obviously impossible. So you need to tell D...
Emacs on Mac OS X Leopard key bindings
...
Swapping CTRL and CAPS LOCK
Go into System Preferences
Enter the Keyboard & Mouse preference pane
In the Keyboard tab, click Modifier Keys...
Swap the actions for Caps Lock and Control.
Using ALT/OPTION as META
In the menu bar, click Terminal
Click Preferences....
What is the difference between old style and new style classes in Python?
...(x) is always <type
'instance'>.
This reflects the fact that all old-style instances, independently of
their class, are implemented with a single built-in type, called
instance.
New-style classes were introduced in Python 2.2 to unify the concepts of class and type.
A new-s...
Is it possible to forward-declare a function in Python?
...rwards is impossible, what about defining it in some other module?
Technically you still define it first, but it's clean.
You could create a recursion like the following:
def foo():
bar()
def bar():
foo()
Python's functions are anonymous just like values are anonymous, yet they can be ...
Android: upgrading DB version and adding new table
...
1. About onCreate() and onUpgrade()
onCreate(..) is called whenever the app is freshly installed. onUpgrade is called whenever the app is upgraded and launched and the database version is not the same.
2. Incrementing the db version
You need a constructor like:
MyOpenHelp...
How to configure encoding in Maven?
...en I run maven install on my multi module maven project I always get the following output:
6 Answers
...
Creating a config file in PHP
...ne simple but elegant way is to create a config.php file (or whatever you call it) that just returns an array:
<?php
return array(
'host' => 'localhost',
'username' => 'root',
);
And then:
$configs = include('config.php');
...
File Upload ASP.NET MVC 3.0
...maxRequestLength="x" /> in your web.config, where x is the number of KB allowed for upload.
– rsbarro
May 22 '11 at 20:33
86
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The required anti-forgery form field “__RequestVerificationToken” is not present Error in user Regis
...rs typing http were getting this error, putting in a rewrite rule to force all to https://{HTTP_HOST}/{R:1} fixed it
– user1069816
Mar 24 '16 at 15:30
...