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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 use Global Variables in C#?
...er the behavior of static variables declared inside, but it doesn't look really useful.
– Tommaso Belluzzo
Feb 2 at 18:01
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html select option separator
...on>First</option>
</optgroup>
<optgroup label="_________">
<option>Second</option>
<option>Third</option>
</optgroup>
</select>
disabled option (a bit better):
<select>
<option>Fir...
“Unknown class in Interface Builder file” error at runtime
...th it, and prints the warning.
By default, Objective-C targets will have -all_load -ObjC flags set by default, which will keep all of the symbols. But I had started with a C++ target, and didn't have that. Nevertheless, I found a way around this, which keeps the linker aggressive.
The hack I was...
CGContextDrawImage draws image upside down when passed UIImage.CGImage
...answered Feb 6 '09 at 20:46
Kendall Helmstetter GelnerKendall Helmstetter Gelner
72.5k2626 gold badges123123 silver badges146146 bronze badges
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How to convert list of tuples to multiple lists?
...
xs, ys = [x for x, y in zs], [y for x, y in zs]
return xs, ys
if __name__ == '__main__':
from timeit import timeit
setup_string='''\
N = 2000000
xs = list(range(1, N))
ys = list(range(N+1, N*2))
zs = list(zip(xs, ys))
from __main__ import t1, t2, t3
'''
print(f'zip:\t\t{timeit(...
Add a property to a JavaScript object using a variable as the name?
...out modifying but it's referenced by other questions that are about dynamically creating objects and so I ended up here and happily benefited from this answer.
– Oliver Lloyd
Oct 29 '16 at 17:40
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How to get the system uptime in Windows? [closed]
...and line utility checks and displays various system statistics such as installation date, installed hotfixes and more.
Open a Command Prompt and type the following command:
systeminfo
You can also narrow down the results to just the line you need:
systeminfo | find "System Boot Time:"
3: By ...
How to base64 encode image in linux bash / shell
...
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 )
...
Display names of all constraints for a table in Oracle SQL
...
You need to query the data dictionary, specifically the USER_CONS_COLUMNS view to see the table columns and corresponding constraints:
SELECT *
FROM user_cons_columns
WHERE table_name = '<your table name>';
FYI, unless you specifically created your table with ...