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What is /dev/null 2>&1?
...standard error as we know whenever a file is opened, the operating system (from kernel) returns a non-negative integer called a file descriptor. The file descriptor for these files are 0, 1, and 2, respectively.
So 2>&1 simply says redirect standard error to standard output.
& means ...
How can I give eclipse more memory than 512M?
...w to. PermSize is the area where class/method objects are stored, separate from the heap.
– jfritz42
Mar 14 '14 at 18:59
...
Run a Java Application as a Service on Linux
...
echo $PID > pid.txt
Then your stop script stop.sh would read the PID from the file and kill the application:
PID=$(cat pid.txt)
kill $PID
Of course I've left out some details, like checking whether the process exists and removing pid.txt if you're done.
...
Unable to simultaneously satisfy constraints, will attempt to recover by breaking constraint
...dditionally you can find NSLayoutConstraint in view hierarchy. Since it is selected in View, it selected in Navigator also.
If you need you may also print it on console using address pointer:
(lldb) po 0x17dce920
<UIView: 0x17dce920; frame = (10 30; 300 24.5); autoresize = RM+BM; layer = <...
Can Selenium Webdriver open browser windows silently in background?
...t install Xvfb:
sudo apt-get install xvfb
then install PyVirtualDisplay from Pypi:
pip install pyvirtualdisplay
Sample Selenium script in Python in a headless mode with PyVirtualDisplay:
#!/usr/bin/env python
from pyvirtualdisplay import Display
from selenium import webdriver
...
Python: Tuples/dictionaries as keys, select, sort
...d like to organize them in a data structure in Python that allows for easy selection and sorting. My idea was to put them into a dictionary with tuples as keys, e.g.,
...
Show an image preview before upload
... code snippet in the HTML example below filters out images from the user's selection and renders selected files into multiple thumbnail previews:
function handleFileSelect(evt) {
var files = evt.target.files;
// Loop through the FileList and render image files as thumbnails.
fo...
MySQL - ORDER BY values within IN()
...
SELECT id, name
FROM mytable
WHERE name IN ('B', 'A', 'D', 'E', 'C')
ORDER BY FIELD(name, 'B', 'A', 'D', 'E', 'C')
The FIELD function returns the position of the first string in the remaining list of strings.
However, it i...
Best approach to real time http streaming to HTML5 video client
...for the detailed background and pro/cons about the various options. I have selected this answer as the accepted one as the outline of the concepts are more important than the specific fix which I found to answer the original question. Good luck with the bounty!
– deandob
...
Where are my postgres *.conf files?
...alives_idle = 0 # TCP_KEEPIDLE, in seconds;
# 0 selects the system default
#tcp_keepalives_interval = 0 # TCP_KEEPINTVL, in seconds;
# 0 selects the system default
#tcp_keepalives_count = 0 # TCP_KEEPCNT;
# 0 selects the...