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Grep and Sed Equivalent for XML Command Line Processing
...a will be in files of single line records like csv. It's really simple to handle this data with grep and sed . But I have to deal with XML often, so I'd really like a way to script access to that XML data via the command line. What are the best tools?
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Check Whether a User Exists
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You can also check user by id command.
id -u name gives you the id of that user.
if the user doesn't exist, you got command return value ($?)1
And as other answers pointed out: if all you want is just to check if the user exists, use if with id directly, as i...
When is CRC more appropriate to use than MD5/SHA1?
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CRC works fine for detecting random errors in data that might occur, for example, from network interference, line noise, distortion, etc.
CRC is computationally much less complex than MD5 or SHA1. Using a hash function like MD5 is probably overkill for r...
How to update a plot in matplotlib?
...ure here. I allow the user to specify the units in the time scale (x-axis) and then I recalculate and call this function plots() . I want the plot to simply update, not append another plot to the figure.
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How to place and center text in an SVG rectangle
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An easy solution to center text horizontally and vertically in SVG:
Set the position of the text to the absolute center of the element in which you want to center it:
If it's the parent, you could just do x="50%" y ="50%".
If it's another element, x would be the x o...
What's quicker and better to determine if an array key exists in PHP?
... if the value is NULL.
Whereas
isset() will return false if the key exist and value is NULL.
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Default text which won't be shown in drop-down list
...orked perfectly fine for me so I made my research in order to avoid any Js and CSS, but just sticking with HTML.
Adding a value of selected to the item we want to appear as a header forces it to show in the first place as a placeholder.
Something like:
<option selected disabled>Choose here&l...
What is the difference between user and kernel modes in operating systems?
What are the differences between User Mode and Kernel Mode, why and how do you activate either of them, and what are their use cases?
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How do you manage databases in development, test, and production?
...a hard time trying to find good examples of how to manage database schemas and data between development, test, and production servers.
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How to pull remote branch from somebody else's repo
...ich somebody has forked. On their fork, they've created a new branch "foo" and made some changes. How do I pull their "foo" into a new branch also named "foo" in my repo?
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