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How to insert a text at the beginning of a file?
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To actually insert a new line: sed -i '1s/^/<added text> \n/' file
– jslatts
Sep 17 '13 at 13:27
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One line if-condition-assignment
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I don't think this is possible in Python, since what you're actually trying to do probably gets expanded to something like this:
num1 = 20 if someBoolValue else num1
If you exclude else num1, you'll receive a syntax error since I'm quite sure that the assignment must actually return so...
Difference between Statement and PreparedStatement
...nt:
Precompilation and DB-side caching of the SQL statement leads to overall faster execution and the ability to reuse the same SQL statement in batches.
Automatic prevention of SQL injection attacks by builtin escaping of quotes and other special characters. Note that this requires that you use a...
How to grant permission to users for a directory using command line in Windows?
...s instead. This is how you grant John full control over D:\test folder and all its subfolders:
C:\>icacls "D:\test" /grant John:(OI)(CI)F /T
According do MS documentation:
F = Full Control
CI = Container Inherit - This flag indicates that subordinate containers will inherit this ACE.
OI = Ob...
string.Format() giving “Input string is not in correct format”
... message "Input string was not in correct format" was not helpful to me at all. I thought one of my parameters was null or something.
– styfle
Aug 10 '12 at 16:59
add a commen...
How can I check if a scrollbar is visible?
...s been shrunk by the horizontal scroll bar height.
– Ally
Jul 3 '12 at 10:36
why you have defined same function two ti...
Can't seem to discard changes in Git
...d check out had changes that I couldn't discard. Long story short, I tried all of the above, nothing worked. This is what I did to get things back to normal (on a Mac):
Completely remove the autocrlf & safecrlf settings from ~/.gitconfig
Completely remove the autocrlf & safecrlf settings fr...
With MySQL, how can I generate a column containing the record index in a table?
...l l
JOIN (SELECT @curRow := 0) r;
The JOIN (SELECT @curRow := 0) part allows the variable initialization without requiring a separate SET command.
Test case:
CREATE TABLE league_girl (position int, username varchar(10), score int);
INSERT INTO league_girl VALUES (1, 'a', 10);
INSERT INTO leag...
CSS “and” and “or”
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Are we really still concerned with supporting older versions of IE in 2018? Not even Microsoft does.
– Anomaly
Mar 15 '18 at 12:18
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Why are primes important in cryptography?
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Most basic and general explanation: cryptography is all about number theory, and all integer numbers (except 0 and 1) are made up of primes, so you deal with primes a lot in number theory.
More specifically, some important cryptographic algorithms such as RSA critically depen...