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How do I set a variable to the output of a command in Bash?
...myDate '2000-01-01'
946681200
myDate "$(ps ho lstart 1)" boottime
myDate now now ; read utm idl </proc/uptime
myBc "$now-$boottime" uptime
printf "%s\n" ${utm%%.*} $uptime
42134906
42134906
ps --tty pts/20 fw
PID TTY STAT TIME COMMAND
29019 pts/20 Ss 0:00 bash
30944 pt...
In Clojure 1.3, How to read and write a file
I'd like to know the "recommended" way of reading and writing a file in clojure 1.3 .
6 Answers
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In practice, what are the main uses for the new “yield from” syntax in Python 3.3?
... to a generator.
(If we were talking about TCP, yield from g might mean "now temporarily disconnect my client's socket and reconnect it to this other server socket".)
BTW, if you are not sure what sending data to a generator even means, you need to drop everything and read about coroutines first...
String is immutable. What exactly is the meaning? [duplicate]
...efore coming to any conclusion.
This is how String works:
String str = "knowledge";
This, as usual, creates a string containing "knowledge" and assigns it a reference str. Simple enough? Lets perform some more functions:
String s = str; // assigns a new reference to the same string "knowle...
“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
...e']) ? $_POST['value'] : '';
This has become much cleaner as of PHP 7.0, now you can use the null coalesce operator:
// Null coalesce operator - No need to explicitly initialize the variable.
$value = $_POST['value'] ?? '';
Set a custom error handler for E_NOTICE and redirect the messages away f...
How to remove/delete a large file from commit history in Git repository?
...ry. You can then use git gc to clean away the dead data:
$ git gc --prune=now --aggressive
The BFG is typically at least 10-50x faster than running git-filter-branch, and generally easier to use.
Full disclosure: I'm the author of the BFG Repo-Cleaner.
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Difference between volatile and synchronized in Java
...ariables cannot be reordered with each other. The difference is that it is now no longer so easy to reorder normal field accesses around them. Writing to a volatile field has the same memory effect as a monitor release, and reading from a volatile field has the same memory effect as a monitor acquir...
Exclude folder from search but not from the project list
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I think this answer is out dated now. Setting > Project Settings > Scopes doesnt seem to exist
– Andrew
Dec 16 '16 at 13:47
3
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Should MySQL have its timezone set to UTC?
...e server as long as you have the time set right for the current timezone, know the timezone of the datetime columns that you store, and are aware of the issues with daylight savings time.
On the other hand if you have control of the timezones of the servers you work with then you can have everythin...
string sanitizer for filename
...at will sanitize a string and make it ready to use for a filename. Anyone know of a handy one?
17 Answers
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