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How to open, read, and write from serial port in C?
I am a little bit confused about reading and writing to a serial port. I have a USB device in Linux that uses the FTDI USB serial device converter driver. When I plug it in, it creates: /dev/ttyUSB1.
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How to check if DST (Daylight Saving Time) is in effect, and if so, the offset?
...code uses the fact that getTimezoneOffset returns a greater value during Standard Time versus Daylight Saving Time (DST). Thus it determines the expected output during Standard Time, and it compares whether the output of the given date the same (Standard) or less (DST).
Note that getTimezoneOffset...
Multiple left-hand assignment with JavaScript
...e right most before the left most. so var var1=var2 happens after var3 = 1 and after var2 = var3. it's like var3=1; var2=var3; var var1=var2
– gcb
Jan 29 '13 at 18:51
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do..end vs curly braces for blocks in Ruby
...worker who is actively trying to convince me that I should not use do..end and instead use curly braces for defining multiline blocks in Ruby.
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Replace all 0 values to NA
...ays in ?'NULL',
NULL represents the null object in R
which is unique and, I guess, can be seen as the most uninformative and empty object.1 Then it becomes not so surprising that
data.frame(x = c(1, NULL, 2))
# x
# 1 1
# 2 2
That is, R does not reserve any space for this null object.2 Mea...
Is it safe to use -1 to set all bits to true?
...times have surprising behavior because you will have to have the right operand type. Only then you will get the most high value of an unsigned type.
For an example of a possible surprise, consider this one:
unsigned long a = ~0u;
It won't necessarily store a pattern with all bits 1 into a. But ...
Booleans, conditional operators and autoboxing
...time:
E1: `true ? returnsNull() : false` - boolean (auto-unboxing 2nd operand to boolean)
E2: `true ? null : false` - Boolean (autoboxing of 3rd operand to Boolean)
See Java Language Specification, section 15.25 Conditional Operator ? :
For E1, the types of the 2nd and 3rd operands are Boolean...
A semantics for Bash scripts?
...ripts that appear to work. However, I don't really know what's going on, and I was hoping for a more formal introduction to Bash as a programming language. For example: What is the evaluation order? what are the scoping rules? What is the typing discipline, e.g. is everything a string? What is the...
JSON left out Infinity and NaN; JSON status in ECMAScript?
Any idea why JSON left out NaN and +/- Infinity? It puts Javascript in the strange situation where objects that would otherwise be serializable, are not, if they contain NaN or +/- infinity values.
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How do I put an already-running process under nohup?
I have a process that is already running for a long time and don't want to end it.
11 Answers
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