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Difference between malloc and calloc?
..., while malloc() leaves the memory uninitialized.
For large allocations, most calloc implementations under mainstream OSes will get known-zeroed pages from the OS (e.g. via POSIX mmap(MAP_ANONYMOUS) or Windows VirtualAlloc) so it doesn't need to write them in user-space. This is how normal malloc ...
In Python script, how do I set PYTHONPATH?
...
It has been many years since this answer was posted, but I still want to add that if you want to make sure that Python checks the new directory before all of the others when importing, you should put the new directory first in the list, as in sys.path.insert(0, '/path/to...
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 ...
How to remove the hash from window.location (URL) with JavaScript without page refresh?
...
This will remove the trailing hash as well.
eg: http://test.com/123#abc -> http://test.com/123
if(window.history.pushState) {
window.history.pushState('', '/', window.location.pathname)
} else {
window.location.hash = '';
}
...
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...
AngularJS: Service vs provider vs factory
...ided code.
Here's a great further explanation by Misko:
provide.value('a', 123);
function Controller(a) {
expect(a).toEqual(123);
}
In this case the injector simply returns the value as is. But what if you want to compute the value? Then use a factory
provide.factory('b', function(a) {
return ...
How can I get the concatenation of two lists in Python without modifying either one? [duplicate]
...;>> sum([(1,2), (1,), ()], ())
(1, 2, 1)
>>> sum([Counter('123'), Counter('234'), Counter('345')], Counter())
Counter({'1':1, '2':2, '3':3, '4':2, '5':1})
>>> sum([True, True, False], False)
2
With the notable exception of strings:
>>> sum(['123', '345', '567'],...
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
...
Please explain some of Paul Graham's points on Lisp
...)
;; this is the interesting bit:
(println (str/replace-re #"\d+" "FOO" "a123b4c56"))
This snippet of Clojure code prints out aFOObFOOcFOO. Note that Clojure arguably does not fully satisfy the fourth point on your list, since read-time is not really open to user code; I will discuss what it would...
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 ...