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How to verify if a file exists in a batch file?
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You can use IF EXIST to check for a file:
IF EXIST "filename" (
REM Do one thing
) ELSE (
REM Do another thing
)
If you do not need an "else", you can do something like this:
set __myVariable=
IF EXIST "C:\folder with space\myfile.txt" set __myVari...
Why does sun.misc.Unsafe exist, and how can it be used in the real world?
...n make real JNI calls into native code that contains special instructions for CAS
read more about CAS here http://en.wikipedia.org/wiki/Compare-and-swap
The sun.misc.Unsafe functionality of the host VM can be used to allocate uninitialized objects and then interpret the constructor invocation as an...
Threads vs Processes in Linux
...I am suspicious, because it seems like threads could give a pretty big performance gain in some situations.
14 Answers
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Redefining NULL
I'm writing C code for a system where address 0x0000 is valid and contains port I/O. Therefore, any possible bugs that access a NULL pointer will remain undetected and at the same time cause dangerous behaviour.
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Null or default comparison of generic argument in C#
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To avoid boxing, the best way to compare generics for equality is with EqualityComparer<T>.Default. This respects IEquatable<T> (without boxing) as well as object.Equals, and handles all the Nullable<T> "lifted" nuances. Hence:
if(EqualityComparer<T>....
Node.js create folder or use existing
...le.
$ npm install mkdirp
Use it to run function that requires the directory. Callback is called after path is created or if path did already exists. Error err is set if mkdirp failed to create directory path.
var mkdirp = require('mkdirp');
mkdirp('/tmp/some/path/foo', function(err) {
// p...
git diff two files on same branch, same commit
sorry if this question exists, I surprisingly could not find it :/
6 Answers
6
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How to remove local (untracked) files from the current Git working tree
How do you delete untracked local files from your current working tree?
38 Answers
38
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Which is more preferable to use: lambda functions or nested functions ('def')?
...ons but sometimes use nested functions that seem to provide the same behavior.
16 Answers
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Why use Ruby instead of Smalltalk? [closed]
...n Ruby and Smalltalk -- maglev is a testament to that. Despite having a more unusual syntax, Smalltalk has all (if not more) of the object-oriented beauty of Ruby.
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