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How to tell if a string is not defined in a Bash shell script
If I want to check for the null string I would do
12 Answers
12
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Arduino Sketch upload issue - avrdude: stk500_recv(): programmer is not responding
I have an Arduino Duemilanove with an ATmega328 . I am working on Ubuntu 12.04 (Precise Pangolin), and the Arduino IDE's version is 1.0. Recently, I tried to upload a few of the sample sketches onto it, such as the Blink one. However, none of my attempts are working and they result in the same e...
Evaluating a mathematical expression in a string
This returns the following error:
11 Answers
11
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How do I keep Python print from adding newlines or spaces? [duplicate]
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import sys
sys.stdout.write('h')
sys.stdout.flush()
sys.stdout.write('m')
sys.stdout.flush()
You need to call sys.stdout.flush() because otherwise it will hold the text in a buffer and you won't see it.
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Loop through an array of strings in Bash?
...r=("element1" "element2" "element3")
## now loop through the above array
for i in "${arr[@]}"
do
echo "$i"
# or do whatever with individual element of the array
done
# You can access them using echo "${arr[0]}", "${arr[1]}" also
Also works for multi-line array declaration
declare -a arr=(...
Pros and Cons of Interface constants [closed]
...ou can avoid the use of constants by implementing other patterns (strategy or perhaps flyweight), there is something to be said for not needing a half dozen other classes to represent a concept. I think what it boils down to, is how likely is there a need for other constants. In other words, is th...
Python subprocess.Popen “OSError: [Errno 12] Cannot allocate memory”
Note: This question was originally asked here but the bounty time expired even though an acceptable answer was not actually found. I am re-asking this question including all details provided in the original question.
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vector vs. list in STL
...ut the end of a sequence repeatedly.
Check out the complexity guarantees for each different type of container:
What are the complexity guarantees of the standard containers?
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Function vs. Stored Procedure in SQL Server
I've been learning Functions and Stored Procedure for quite a while but I don't know why and when I should use a function or a stored procedure. They look same to me, maybe because I am kinda newbie about that.
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check android application is in foreground or not? [duplicate]
I went through a lot of answers for this question.But it's all about single activity..How to check whether the whole app is running in foreground or not ?
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