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Can not connect to local PostgreSQL
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This really looks like a file permissions error. Unix domain sockets are files and have user permissions just like any other. It looks as though the OSX user attempting to access the database does not have file permissions to acce...
Signed to unsigned conversion in C - is it always safe?
...herwise, if the type of the operand with signed integer type can represent all of the values of the type of the operand with unsigned integer type, then the operand with unsigned integer type is converted to the type of the operand with signed integer type.
Otherwise, both operands are converted t...
How to print struct variables in console?
... @fnr If you have a JSON document, you would need to unmarshall it, before being able to print its field.
– VonC
Jul 1 '14 at 14:16
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How do I execute a command and get the output of the command within C++ using POSIX?
...use the C stdio API, I prefer the iostreams API. popen requires you to manually clean up the FILE handle, pstreams do that automatically. popen only accepts a const char* for the argument, which requires care to avoid shell injection attacks, pstreams allows you to pass a vector of strings similar t...
How to know/change current directory in Python shell?
...now how to change.
edit
Under Windows:
set PYTHONPATH=%PYTHONPATH%;C:\My_python_lib
(taken from http://docs.python.org/using/windows.html)
edit 2
... and even better: use virtualenv and virtualenv_wrapper, this will allow you to create a development environment where you can add module paths ...
SVN: Is there a way to mark a file as “do not commit”?
...rtoiseSVN has a built in changelist, "ignore-on-commit", which is automatically excluded from commits. The command-line client does not have this, so you need to use multiple changelists to accomplish this same behavior (with caveats):
one for work you want to commit [work]
one for things you want...
Random row selection in Pandas dataframe
... Thanks @eumiro. I also worked out that df.ix[np.random.random_integers(0, len(df), 10)] would also work.
– John
Apr 10 '13 at 10:58
7
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Multiline bash commands in makefile
...colon:
foo:
for i in `find`; \
do \
all="$$all $$i"; \
done; \
gcc $$all
But if you just want to take the whole list returned by the find invocation and pass it to gcc, you actually don't necessarily need a multiline command:
foo:
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Why is creating a Thread said to be expensive?
... there is a fair bit of work involved:
A large block of memory has to be allocated and initialized for the thread stack.
System calls need to be made to create / register the native thread with the host OS.
Descriptors need to be created, initialized and added to JVM-internal data structures.
It...
Array.push() if does not exist?
... it doesn't then just push the item into the array:
var newItem = "NEW_ITEM_TO_ARRAY";
var array = ["OLD_ITEM_1", "OLD_ITEM_2"];
array.indexOf(newItem) === -1 ? array.push(newItem) : console.log("This item already exists");
console.log(array)
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