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Negation in Python
...herefore just replace your ! with not.
For your example, do this:
if not os.path.exists("/usr/share/sounds/blues") :
proc = subprocess.Popen(["mkdir", "/usr/share/sounds/blues"])
proc.wait()
For your specific example (as Neil said in the comments), you don't have to use the subprocess ...
Get last n lines of a file, similar to tail
...ctually accurate, you make the block size 2048 and you'll tail 20 lines almost immediately.
Also, I don't burn a lot of brain calories trying to finesse alignment with physical OS blocks. Using these high-level I/O packages, I doubt you'll see any performance consequence of trying to align on OS b...
What exactly is Python's file.flush() doing?
...t has been "permanently" stored on disk.
To do that, you need to call the os.fsync method which ensures all operating system buffers are synchronized with the storage devices they're for, in other words, that method will copy data from the operating system buffers to the disk.
Typically you don't ...
How do I run IDEA IntelliJ on Mac OS X with JDK 7?
I use Mac OS X 10.8.2, and use JDK 7. Now I downloaded the latest version of IDEA IntelliJ, 11. But it doesn't seem to start without JDK 6. Is there any workaround?
...
How can I programmatically determine if my app is running in the iphone simulator?
...r "Compiling source code conditionally"
The relevant definition is TARGET_OS_SIMULATOR, which is defined in /usr/include/TargetConditionals.h within the iOS framework. On earlier versions of the toolchain, you had to write:
#include "TargetConditionals.h"
but this is no longer necessary on the c...
How to read a file in reverse order?
...
Also, while the posted code does answer the question, we should be careful to close files that we open. The with statement is usually quite painless.
– William
Mar 7 '13 at 14:41
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What is the difference/usage of homebrew, macports or other package installation tools? [closed]
...e application: C + TCL. You don't need Ruby at all. To install Ruby on Mac OS X you might need MacPorts, so just go with MacPorts and you'll be happy.
MacPorts is really stable, in 8 years I never had a problem with it, and my entire Unix ecosystem relay on it.
If you are a PHP developer you can ins...
Simulating tremor (from e.g. Parkinson's Disease) with the mouse on a webpage?
... the same as a shaking hand. With random movement the pointer can drift across the screen. With a shaking hand the pointer is going to vibrate around a central point.
– zzzzBov
Aug 12 '14 at 14:53
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What and where are the stack and heap?
...d. The stack is always reserved in a LIFO (last in first out) order; the most recently reserved block is always the next block to be freed. This makes it really simple to keep track of the stack; freeing a block from the stack is nothing more than adjusting one pointer.
The heap is memory set asi...
How can I get the behavior of GNU's readlink -f on a Mac?
... -f that follows additional links. This doesn't seem to work on Mac and possibly BSD based systems. What would the equivalent be?
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