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What's the difference between Perl's backticks, system, and exec?
...d run simultaneously.
This can be accomplished with open.
It allows you to read STDOUT/STDERR and write to STDIN of your command.
It is platform dependent though.
There are also several modules which can ease this tasks.
There is IPC::Open2 and IPC::Open3 and IPC::Run, as well as
Win32::Process::Cr...
NoSQL - MongoDB vs CouchDB [closed]
...
thus, master-master replication. (!)
MVCC - write operations do not block reads
Previous versions of documents are available
Crash-only (reliable) design
Needs compacting from time to time
Views: embedded map/reduce
Formatting views: lists & shows
Server-side document validation possible
Authen...
Is it ever advantageous to use 'goto' in a language that supports loops and functions? If so, why?
...r using the "goto" statement that I'm aware of (some have spoken to this already):
Cleanly exiting a function
Often in a function, you may allocate resources and need to exit in multiple places. Programmers can simplify their code by putting the resource cleanup code at the end of the function, a...
Where does R store packages?
...
It is a file. Again, read the fine manual, and/or help(Startup).
– Dirk Eddelbuettel
Apr 10 '10 at 22:12
...
MySQL “Group By” and “Order By”
...:
SELECT cur.textID, cur.fromEmail, cur.subject,
cur.timestamp, cur.read
FROM incomingEmails cur
LEFT JOIN incomingEmails next
on cur.fromEmail = next.fromEmail
and cur.timestamp < next.timestamp
WHERE next.timestamp is null
and cur.toUserID = '$userID'
ORDER BY LOWER(cur.fromEmai...
HTML-encoding lost when attribute read from input field
...n the escape templatetag in Django, which I guess is heavily used/tested already, I made this function which does what's needed.
It's arguably simpler (and possibly faster) than any of the workarounds for the whitespace-stripping issue - and it encodes quote marks, which is essential if you're goin...
How to replace an entire line in a text file by line number
... Useless for the interpreter/compiler maybe, but not for a human reading it. @Kyle's code reads nicely left to right; the idiom you used IMO does not, due to the fact that the verb is before the noun.
– Clayton Stanley
Jun 23 '12 at 1:43
...
Longest line in a file
...l commands. Takes filename as first argument:
#!/bin/sh
MAX=0 IFS=
while read -r line; do
if [ ${#line} -gt $MAX ]; then MAX=${#line}; fi
done < "$1"
printf "$MAX\n"
share
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improve this ans...
Nodejs Event Loop
...
I have been personally reading the source code of node.js & v8.
I went into a similar problem like you when I tried to understand node.js architecture in order to write native modules.
What I am posting here is my understanding of node.js and...
What is a difference between
...
So if I read it right, "<? extends E>" requires that "?" is a subclass of "E", and "<? super E>" requires that "E" is a subclass of "?", right?
– El Suscriptor Justiciero
Jun 26 '18 ...