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iOS start Background Thread
... is responsible for setting up the new thread's autorelease pool, run loop and other configuration details – see "Using NSObject to Spawn a Thread" in Apple's Threading Programming Guide.
You'd probably be better off using Grand Central Dispatch, though:
dispatch_async(dispatch_get_global_queue(...
How to find an available port?
...nt to start a server which listen to a port. I can specify port explicitly and it works. But I would like to find a port in an automatic way. In this respect I have two questions.
...
Evaluating a mathematical expression in a string
...ppend(toks[0])
def pushUMinus(self, strg, loc, toks):
if toks and toks[0] == '-':
self.exprStack.append('unary -')
def __init__(self):
"""
expop :: '^'
multop :: '*' | '/'
addop :: '+' | '-'
integer :: ['+' | '-'] '0'..'9'+
...
How to drop SQL default constraint without knowing its name?
...ver, I know the query to check if a default constraint exists for a column and drop a default constraint is:
14 Answers
...
How do you merge two Git repositories?
... rewriting the history as described in other answers.
The git-subtree command is a part of official git-contrib, some packet managers install it by default (OS X Homebrew).
But you might have to install it by yourself in addition to git.
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Linux: compute a single hash for a given folder & contents?
...
If there is a whole directory tree, you're probably better off using find and xargs. One possible command would be
find path/to/folder -type f -print0 | sort -z | xargs -0 sha1sum | sha1sum
And, finally, if you also need to take account of permissions and empty directories:
(find path/to/folde...
Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
I have a pandas DataFrame and I want to delete rows from it where the length of the string in a particular column is greater than 2.
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What is the best way to count “find” results?
...
find <expr> -type f -printf '.' | wc -c
It will be more reliable and faster than counting the lines.
Note that I use the find's printf, not an external command.
Let's bench a bit :
$ ls -1
a
e
l
ll.sh
r
t
y
z
My snippet benchmark :
$ time find -type f -printf '.' | wc -c
8
real ...
How to make blinking/flashing text with CSS 3
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You are first setting opacity: 1; and then you are ending it on 0, so it starts from 0% and ends on 100%, so instead just set opacity to 0 at 50% and the rest will take care of itself.
Demo
.blink_me {
animation: blinker 1s linear infinite;
}
@ke...
How to extract text from a string using sed?
...
That's why, isn't it? Replace whatever comes before and after the match with norhing, then print the whole line.
– tripleee
Jul 19 '12 at 21:01
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