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Bash if [ false ] ; returns true
...e; a non-empty string is an expression that evaluates as true, just as in most other programming languages. false is a command which always fails. (By analogy, true is a command that always succeeds.)
– chepner
Oct 29 '13 at 22:24
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In Python, how do I create a string of n characters in one line of code?
...
This might be a little off the question, but for those interested in the randomness of the generated string, my answer would be:
import os
import string
def _pwd_gen(size=16):
chars = string.letters
chars_len = len(chars)
return str().join(chars[int(ord(c) / 256...
Copy paste text into iOS simulator
...ator's clipboard. They are not the same.
The simulator is simulating an iOS device, with it's own iOS clipboard which apps running on that device (simulator) use via the iOS pup-up select-all/copy/paste UI items.
Completely separate from that: your mac has it's own clipboard and content. The Simu...
Quickly create a large file on a Linux system
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dd from the other answers is a good solution, but it is slow for this purpose. In Linux (and other POSIX systems), we have fallocate, which uses the desired space without having to actually writing to it, works with most modern disk based file systems, very fast:
For example:
fallocate -l 10G gen...
InputStream from a URL
...ur original code uses FileInputStream, which is for accessing file system hosted files.
The constructor you used will attempt to locate a file named a.txt in the www.somewebsite.com subfolder of the current working directory (the value of system property user.dir). The name you provide is resolved ...
Keyboard Interrupts with python's multiprocessing Pool
...ever returns, so the interrupt never happens. KeyboardInterrupt should almost certainly interrupt a condition wait.
Note that this doesn't happen if a timeout is specified; cond.wait(1) will receive the interrupt immediately. So, a workaround is to specify a timeout. To do that, replace
res...
pip installing in global site-packages instead of virtualenv
...ne in the virtualenv folder. Here's how I set up Python3 and virtualenv on OS X Mavericks (10.9.1):
30 Answers
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How to check if command line tools is installed
I have a macbook pro with OS X 10.8.2.
XCode is installed. I know this as it appears in the Applications directory.
There are also the xcodebuild and xcode-select files in /usr/bin
I need to know if the command line tools is installed.
Is there a command for it?
What can I do to see if XCode CLT is ...
What does “for” attribute do in HTML tag?
...re equivalent. What you're describing is more about the UI provided by the OS's handling of drop-down menus, which is tied to the mouse itself.
– Barmar
Feb 8 '16 at 15:06
3
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Meaning of Choreographer messages in Logcat [duplicate]
...ce.
Android view animations internally uses Choreographer for the same purpose: to properly time the animations and possibly improve performance.
Since Choreographer is told about every vsync events, it can tell if one of the Runnables passed along by the Choreographer.post* apis doesn't finish in o...