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xpath find if node exists
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edited Apr 20 '09 at 11:33
answered Apr 20 '09 at 11:26
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How do I delete rows in a data frame?
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A5C1D2H2I1M1N2O1R2T1A5C1D2H2I1M1N2O1R2T1
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What is a semaphore?
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404
Think of semaphores as bouncers at a nightclub. There are a dedicated number of people that are...
Image resizing client-side with JavaScript before upload to the server
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Here's a gist which does this:
https://gist.github.com/dcollien/312bce1270a5f511bf4a
(an es6 version, and a .js version which can be included in a script tag)
You can use it as follows:
<input type="file" id="select">
<img id="preview">
<script>
document.getElementById('select...
MAMP Pro 3.05 on Mavericks updated to Yosemite - Apache does not start
I have been running MAMP Pro 3.05 successfully in Yosemite up to DP4 on a partition that was a clean install of Yosemite.
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How to handle Handler messages when activity/fragment is paused
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+50
Although the Android operating system does not appear to have a mechanism that sufficiently addresses your problem I believe this patt...
What is the purpose of “&&” in a shell command?
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409
&& lets you do something based on whether the previous command completed successfully -...
form serialize javascript (no framework)
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Cimbali
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answered Jul 26 '12 at 1:46
LusitanianLusitanian
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Is it safe to parse a /proc/ file?
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+400
In general, no. (So most of the answers here are wrong.) It might be safe, depending on what property you want. But it's easy to end ...
While loop to test if a file exists in bash
...xists by adding:
while [ ! -f /tmp/list.txt ]
do
sleep 2 # or less like 0.2
done
ls -l /tmp/list.txt
You might also make sure that you're using a Bash (or related) shell by typing 'echo $SHELL'. I think that CSH and TCSH use a slightly different semantic for this loop.
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