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Accessing last x characters of a string in Bash
...of string:
${string: -3}
or
${string:(-3)}
(mind the space between : and -3 in the first form).
Please refer to the Shell Parameter Expansion in the reference manual:
${parameter:offset}
${parameter:offset:length}
Expands to up to length characters of parameter starting at the character
spe...
How can I suppress all output from a command using Bash?
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The following sends standard output to the null device (bit bucket).
scriptname >/dev/null
And if you also want error messages to be sent there, use one of (the first may not work in all shells):
scriptname &>/dev/null
scriptname >...
How do you implement a class in C? [closed]
Assuming I have to use C (no C++ or object oriented compilers) and I don't have dynamic memory allocation, what are some techniques I can use to implement a class, or a good approximation of a class? Is it always a good idea to isolate the "class" to a separate file? Assume that we can preallocate t...
What is the difference between ng-if and ng-show/ng-hide
I'm trying to understand the difference between ng-if and ng-show / ng-hide , but they look the same to me.
12 Answers
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What are the differences between Autotools, Cmake and Scons?
What are the differences between Autotools, Cmake and Scons?
5 Answers
5
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Deleting rows with MySQL LEFT JOIN
... one for job deadlines, one for describe a job. Each job can take a status and some statuses means the jobs' deadlines must be deleted from the other table.
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How might I convert a double to the nearest integer value?
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double d = 1.234;
int i = Convert.ToInt32(d);
Reference
Handles rounding like so:
rounded to the nearest 32-bit signed integer. If value is halfway
between two whole numbers, the even number is returned; that is, 4.5
is converted to 4, and 5.5 is converted to 6.
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What is the difference between a symbolic link and a hard link?
Recently I was asked this during a job interview. I was honest and said I knew how a symbolic link behaves and how to create one, but do not understand the use of a hard link and how it differs from a symbolic one.
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What does “static” mean in C?
...l for cases where a function needs to keep some state between invocations, and you don't want to use global variables. Beware, however, this feature should be used very sparingly - it makes your code not thread-safe and harder to understand.
(2) Is used widely as an "access control" feature. If you...
How to pip install a package with min and max version range?
...tall a package with both a minimum version ( pip install package>=0.2 ) and a maximum version which should never be installed (theoretical api: pip install package<0.3 ).
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