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Git merge master into feature branch
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How does the NSAutoreleasePool autorelease pool work?
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Static constant string (class member)
...d::string's all the time too. The overhead is negligible, but you have far more options and are much less likely to write some fool things like "magic" == A::RECTANGLE only to compare their address...
– Matthieu M.
Oct 14 '09 at 14:24
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Entity Framework and Connection Pooling
...onnnection pooling in connection string if you don't want to use it. (read more about SQL Server Connection Pooling (ADO.NET))
Never ever use global context. ObjectContext internally implements several patterns including Identity Map and Unit of Work. Impact of using global context is different per ...
What do hjust and vjust do when making a plot using ggplot?
...es the y-axis text). (This is, in my view, unfortunate. It would be much more useful to have the alignment relative to the axis.)
DF <- data.frame(x=LETTERS[1:3],y=1:3)
p <- ggplot(DF, aes(x,y)) + geom_point() +
ylab("Very long label for y") +
theme(axis.title.y=element_text(angle=...
Dealing with “java.lang.OutOfMemoryError: PermGen space” error
...his option brings down performance. It makes each request take three times more time than usual on our systems. Use with care.
– Eldelshell
Sep 3 '10 at 9:16
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Create a .csv file with values from a Python list
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Run cron job only if it isn't already running
... It's better.
Now you don't have to write the code yourself. Check out more reasons here: https://serverfault.com/a/82863
/usr/bin/flock -n /tmp/my.lockfile /usr/local/bin/my_script
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How do I write stderr to a file while using “tee” with a pipe?
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Test if remote TCP port is open from a shell script
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As pointed by B. Rhodes, nc (netcat) will do the job. A more compact way to use it:
nc -z <host> <port>
That way nc will only check if the port is open, exiting with 0 on success, 1 on failure.
For a quick interactive check (with a 5 seconds timeout):
nc -z -v -w5 <...