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How do I pass a string into subprocess.Popen (using the stdin argument)?
...current Python 3 version, you could use subprocess.run, to pass input as a string to an external command and get its exit status, and its output as a string back in one call:
#!/usr/bin/env python3
from subprocess import run, PIPE
p = run(['grep', 'f'], stdout=PIPE,
input='one\ntwo\nthree\...
How do I write outputs to the Log in Android?
...ery long. You can define somewhere in your class:
private static final String TAG = "myApp";
and use it when debugging
Log.v(TAG, "did something");
You can apply as well a Filter to only search for the tag.
sha...
Reading my own Jar's Manifest
...u load the manifest from there. For example,
Class clazz = MyClass.class;
String className = clazz.getSimpleName() + ".class";
String classPath = clazz.getResource(className).toString();
if (!classPath.startsWith("jar")) {
// Class not from JAR
return;
}
String manifestPath = classPath.substrin...
jQuery: Get selected element tag name
...
Note that the string that's returned is in CAPITAL LETTERS. This'll be a gotcha if you're trying to compare it to "div" or "a" for example.
– Hartley Brody
Apr 29 '14 at 23:41
...
Open a link in browser with java button? [duplicate]
... I "worked around" it by calling new ProcessBuilder("x-www-browser", uri.toString());. You would think that if there were security restrictions, the ProcessBuilder call would not work. But it does work. I have no idea why desktop.browse(uri) doesn't work, but I have seen that it doesn't work for a l...
parseInt vs unary plus, when to use which?
...lete set of cases
Well, here are a few differences I know of:
An empty string "" evaluates to a 0, while parseInt evaluates it to NaN. IMO, a blank string should be a NaN.
+'' === 0; //true
isNaN(parseInt('',10)); //true
The unary + acts more like parseFloat since it also acce...
Can I grep only the first n lines of a file?
... be faster you're solution is not searching for regexps but only for fixed strings. awk '{ if ( NR <= 10 ) { if( $0 ~ "YOUR_REGEXP") { print } } else { exit; } }' textfile does.
– Zsolt Botykai
Jan 7 '12 at 10:06
...
PostgreSQL Autoincrement
...other integer data type, such as smallint.
Example :
CREATE SEQUENCE user_id_seq;
CREATE TABLE user (
user_id smallint NOT NULL DEFAULT nextval('user_id_seq')
);
ALTER SEQUENCE user_id_seq OWNED BY user.user_id;
Better to use your own data type, rather than user serial data type.
...
How to find if a given key exists in a C++ std::map
... us std::map::contains to do that.
#include <iostream>
#include <string>
#include <map>
int main()
{
std::map<int, std::string> example = {{1, "One"}, {2, "Two"},
{3, "Three"}, {42, "Don\'t Panic!!!"}};
if(example.contains(42))...
Rails migrations: self.up and self.down versus change
...d only delete this column on down
def up
add_column :users, :location, :string
User.update_all(location: 'Minsk')
end
def down
remove_column :users, :location
end
But:
You had to avoid using change method which allows to save some time. For example, if you didn’t need to update column v...
