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How to avoid isset() and empty()
...undefined" and "undefined offset" messages when running on the E_NOTICE error level, because the existence of variables is not explicitly checked using isset() and consorts.
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Match everything except for specified strings
I know that the following regex will match "red", "green", or "blue".
7 Answers
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Why does ENOENT mean “No such file or directory”?
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It's an abbreviation of Error NO ENTry (or Error NO ENTity), and can actually be used for more than files/directories.
It's abbreviated because C compilers at the dawn of time didn't support more than 8 characters in symbols.
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How to identify if a webpage is being loaded inside an iframe or directly into the browser window?
...me based facebook app. Now I want to use the same html page to render the normal website as well as the canvas page within facebook. I want to know if I can determine whether the page has been loaded inside the iframe or directly in the browser?
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Checking from shell script if a directory contains files
From a shell script, how do I check if a directory contains files?
26 Answers
26
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Checking if a string is empty or null in Java [duplicate]
I'm parsing HTML data. The String may be null or empty, when the word to parse does not match.
5 Answers
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What are the undocumented features and limitations of the Windows FINDSTR command?
The Windows FINDSTR command is horribly documented. There is very basic command line help available through FINDSTR /? , or HELP FINDSTR , but it is woefully inadequate. There is a wee bit more documentation online at https://docs.microsoft.com/en-us/windows-server/administration/windows-commands...
What are rvalues, lvalues, xvalues, glvalues, and prvalues?
In C++03, an expression is either an rvalue or an lvalue .
11 Answers
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In the shell, what does “ 2>&1 ” mean?
...hell, if I want to combine stderr and stdout into the stdout stream for further manipulation, I can append the following on the end of my command:
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Logic to test that 3 of 4 are True
...s to be true, it seems natural to me that the value 3 appears somewhere.
For instance, in C++:
if ((int)a + (int)b + (int)c + (int)d == 3)
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This is well defined in C++: the standard (§4.7/4) indicates that converting bool to int gives the expected values 0 or 1.
In Java and C#, you can ...