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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 ...
Log exception with traceback
...send STDERR to a file using whatever shell you're using to run your Python script. In a Bash script, you can do this with output redirection, as described in the BASH guide.
Examples
Append errors to file, other output to the terminal:
./test.py 2>> mylog.log
Overwrite file with interleav...
How to make pipes work with Runtime.exec()?
...
Write a script, and execute the script instead of separate commands.
Pipe is a part of the shell, so you can also do something like this:
String[] cmd = {
"/bin/sh",
"-c",
"ls /etc | grep release"
};
Process p = Runtime.getRuntime...
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 ...
Can existing virtualenv be upgraded gracefully?
...
Thanks! I tried your method and see that the 'activate' script is updated, but the old version remains (please see the revised question). Are you able to provide an example?
– Matt Norris
Jan 31 '10 at 14:13
...
Delete empty lines using sed
...ys 0m0.006s Would you know of a nifty way to include this into an awk-script like, e.g., a pattern? awk '/mypattern/ {do stuff...}'
– Bernie Reiter
Feb 27 '17 at 22:17
...
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
...
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 ...