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Pipe output and capture exit status in Bash
I want to execute a long running command in Bash, and both capture its exit status, and tee its output.
15 Answers
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Non-static variable cannot be referenced from a static context
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You must understand the difference between a class and an instance of that class. If you see a car on the street, you know immediately that it's a car even if you can't see which model or type. This is because you compare what you see with t...
Checking if a string is empty or null in Java [duplicate]
...ge Apache Commons StringUtils.isEmpty(str), which checks for empty strings and handles null gracefully.
Example:
System.out.println(StringUtils.isEmpty("")); // true
System.out.println(StringUtils.isEmpty(null)); // true
Google Guava also provides a similar, probably easier-to-read method: Stri...
Should I compile release builds with debug info as “full” or “pdb-only”?
..., or pdb-only. Based on the answer to this question , I believe I understand some of the differences between full and pdb-only. However, which is more appropriate for a release build? If I use "full" will there be performance ramifications? If I use "pdb-only" will it be harder to debug product...
Are the PUT, DELETE, HEAD, etc methods available in most web browsers?
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No. The HTML 5 spec mentions:
The method and formmethod content attributes are enumerated attributes
with the following keywords and states:
The keyword get, mapping to the state GET, indicating the HTTP GET
method. The GET method should only request and re...
When and why should I use fragments in Android applications? [duplicate]
... the different parts of my applications to have their own special behavior and UI, and I don't know how fragments can help. In most cases, I think it is quicker to create 2 different activities (e.g., 1 for tablets and 1 for handsets), and to share the common behaviors and events in a third class.
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What's the difference between a single precision and double precision floating point operation?
What is the difference between a single precision floating point operation and double precision floating operation?
11 Answ...
Can you use a trailing comma in a JSON object?
...ed to worry about all browsers.
In general I try turn the problem around, and add the comma before the actual value, so you end up with code that looks like this:
s.append("[");
for (i = 0; i < 5; ++i) {
if (i) s.append(","); // add the comma only if this isn't the first entry
s.appendF("\"...
MySQL: multiple tables or one table with many columns?
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Any time information is one-to-one (each user has one name and password), then it's probably better to have it one table, since it reduces the number of joins the database will need to do to retrieve results. I think some databases have a limit on the number of columns per table, but...
What is “assert” in JavaScript?
...ssertions (as they're called) are used only in "testing" or "debug" builds and stripped out of production code.
Suppose you had a function that was supposed to always accept a string. You'd want to know if someone called that function with something that wasn't a string. So you might do:
assert(ty...