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How to base64 encode image in linux bash / shell
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You need to use cat to get the contents of the file named 'DSC_0251.JPG', rather than the filename itself.
test="$(cat DSC_0251.JPG | base64)"
However, base64 can read from the file itself:
test=$( base64 DSC_0251.JPG )
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How do I pass extra arguments to a Python decorator?
... it needs to return another function which is the actual decorator:
def my_decorator(param):
def actual_decorator(func):
print("Decorating function {}, with parameter {}".format(func.__name__, param))
return function_wrapper(func) # assume we defined a wrapper somewhere
ret...
How could I use requests in asyncio?
I want to do parallel http request tasks in asyncio , but I find that python-requests would block the event loop of asyncio . I've found aiohttp but it couldn't provide the service of http request using a http proxy.
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getenv() vs. $_ENV in PHP
What is the difference between getenv() and $_ENV ?
6 Answers
6
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How to call C from Swift?
Is there a way to call C routines from Swift?
6 Answers
6
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Export and Import all MySQL databases at one time
I want to keep a backup of all my MySQL databases. I have more than 100 MySQL databases. I want to export all of them at the same time and again import all of them into my MySQL server at one time. How can I do that?
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Bash empty array expansion with `set -u`
...ad. Other patterns, such as ${arr[@]-} or ${arr[@]:0}, are not safe across all major versions of Bash.
As the table below shows, the only expansion that is reliable across all modern-ish Bash versions is ${arr[@]+"${arr[@]}"} (column +"). Of note, several other expansions fail in Bash 4.2, includin...
How to forward declare a template class in namespace std?
...rs. Of course, I know that there are more template params for std::list (allocator I think). But, that is beside the point. Do I have to know the full template declaration of a template class to be able to forward declare it?
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Can I call memcpy() and memmove() with “number of bytes” set to zero?
... the length of the array for a
function, n can have the value zero on a call to that function. Unless explicitly stated
otherwise in the description of a particular function in this subclause, pointer arguments
on such a call shall still have valid values, as described in 7.1.4. On such a call...
How to limit the maximum value of a numeric field in a Django model?
...ormer can be restricted to the number of decimal places stored and the overall number of characters stored, is there any way to restrict it to storing only numbers within a certain range, e.g. 0.0-5.0 ?
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