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How to find the operating system version using JavaScript?
How can I find the OS name and OS version using JavaScript?
13 Answers
13
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How to access environment variable values?
...
Environment variables are accessed through os.environ
import os
print(os.environ['HOME'])
Or you can see a list of all the environment variables using:
os.environ
As sometimes you might need to see a complete list!
# using get will return `None` if a key is not...
java.util.regex - importance of Pattern.compile()?
...ch is really called a lot :)
public class AmountValidator {
//Accept 123 - 123,456 - 123,345.34
private static final String AMOUNT_REGEX="\\d{1,3}(,\\d{3})*(\\.\\d{1,4})?|\\.\\d{1,4}";
//Compile and save the pattern
private static final Pattern AMOUNT_PATTERN = Pattern.compile(AM...
Python list directory, subdirectory, and files
...
Use os.path.join to concatenate the directory and file name:
for path, subdirs, files in os.walk(root):
for name in files:
print os.path.join(path, name)
Note the usage of path and not root in the concatenation, sinc...
How do I check whether a file exists without exceptions?
...open it.
If you're not planning to open the file immediately, you can use os.path.isfile
Return True if path is an existing regular file. This follows symbolic links, so both islink() and isfile() can be true for the same path.
import os.path
os.path.isfile(fname)
if you need to be sure it...
Why catch and rethrow an exception in C#?
...ple, in VB you can do
Try
..
Catch Ex As MyException When Ex.ErrorCode = 123
..
End Try
...which would not handle MyExceptions with different ErrorCode values. In C# prior to v6, you would have to catch and re-throw the MyException if the ErrorCode was not 123:
try
{
...
}
catch(MyExcepti...
Recursive sub folder search and return files in a list python
... are supplied so you can prune it if there are folders that you don't wish os.walk to recurse into.
import os
result = [os.path.join(dp, f) for dp, dn, filenames in os.walk(PATH) for f in filenames if os.path.splitext(f)[1] == '.txt']
Edit:
After the latest downvote, it occurred to me that glob ...
How to know/change current directory in Python shell?
...
You can use the os module.
>>> import os
>>> os.getcwd()
'/home/user'
>>> os.chdir("/tmp/")
>>> os.getcwd()
'/tmp'
But if it's about finding other modules: You can set an environment variable called PYT...
Relative paths in Python
... the file that has the script, you want to do something like this:
import os
dirname = os.path.dirname(__file__)
filename = os.path.join(dirname, 'relative/path/to/file/you/want')
This will give you the absolute path to the file you're looking for. Note that if you're using setuptools, you shoul...
What is boxing and unboxing and what are the trade offs?
...xing is the conversion of a reference type into a value type.
EX: int i = 123;
object o = i;// Boxing
int j = (int)o;// UnBoxing
Value Types are: int, char and structures, enumerations.
Reference Types are:
Classes,interfaces,arrays,strings and objects
...