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How do I use a file grep comparison inside a bash if/else statement?
...t status is 0 if any line was selected, 1 otherwise;
if any error occurs and -q was not given, the exit status is 2.
if grep --quiet MYSQL_ROLE=master /etc/aws/hosts.conf; then
echo exists
else
echo not found
fi
You may want to use a more specific regex, such as ^MYSQL_ROLE=master$, to avo...
Difference between Label and TextBlock
... control. It derives directly from FrameworkElement. Label, on the other hand, derives from ContentControl. This means that Label can:
Be given a custom control template (via the Template property).
Display data other than just a string (via the Content property).
Apply a DataTemplate to its cont...
SQL/mysql - Select distinct/UNIQUE but return all columns?
... MySQL, if that's what you're using.)
You could fetch the distinct fields and stick to picking a single arbitrary row each time.
On some platforms (e.g. PostgreSQL, Oracle, T-SQL) this can be done directly using window functions:
select *
from (
select *,
row_number() over (partition...
Static variables in JavaScript
...);
staticProperty is defined in the MyClass object (which is a function) and has nothing to do with its created instances, JavaScript treats functions as first-class objects, so being an object, you can assign properties to a function.
UPDATE: ES6 introduced the ability to declare classes through...
Google Maps v2 - set both my location and zoom in
...s, does anyone know how to set google maps up, to open up both my location and in a zoomed-in view?
11 Answers
...
How to unzip files programmatically in Android?
... need a small code snippet which unzips a few files from a given .zip file and gives the separate files according to the format they were in the zipped file. Please post your knowledge and help me out.
...
How do I change the default port (9000) that Play uses when I execute the “run” command?
...used by the play framework in development mode when issueing the "run" command on the play console.
21 Answers
...
How to enter command with password for git pull?
I want to do this command in one line:
6 Answers
6
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Force unmount of NFS-mounted directory [closed]
... @Daniel: sure, but it is a Linux question (tagged as such even), and Linux does have it.
– Jürgen A. Erhard
Jul 4 '11 at 13:05
5
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The performance impact of using instanceof in Java
I am working on an application and one design approach involves extremely heavy use of the instanceof operator. While I know that OO design generally tries to avoid using instanceof , that is a different story and this question is purely related to performance. I was wondering if there is any per...