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Efficiently test if a port is open on Linux?
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14 Answers
14
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String comparison in bash. [[: not found
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165
[[ is a bash-builtin. Your /bin/bash doesn't seem to be an actual bash.
From a comment:
Add #!...
Internet Explorer 11 detection
I know IE 11 has different user agent string than all other IE
11 Answers
11
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PostgreSQL disable more output
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251
To disable pagination but retain the output, use:
\pset pager off
To remember this setting, a...
How do detect Android Tablets in general. Useragent?
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15 Answers
15
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serve current directory from command line
...o remember, so I just have this in my .bashrc:
function serve {
port="${1:-3000}"
ruby -run -e httpd . -p $port
}
It serves the current directory on port 3000 by default, but you can also specify the port:
~ $ cd tmp
~/tmp $ serve # ~/tmp served on port 3000
~/tmp $ cd ../www
~/www $ se...
Omit rows containing specific column of NA
...ses function and put it into a function thusly:
DF <- data.frame(x = c(1, 2, 3), y = c(0, 10, NA), z=c(NA, 33, 22))
completeFun <- function(data, desiredCols) {
completeVec <- complete.cases(data[, desiredCols])
return(data[completeVec, ])
}
completeFun(DF, "y")
# x y z
# 1 1 0 ...
Dynamically creating keys in a JavaScript associative array
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144
Use the first example. If the key doesn't exist it will be added.
var a = new Array();
a['na...
SQLite INSERT - ON DUPLICATE KEY UPDATE (UPSERT)
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31
Since 3.24.0 SQLite also supports upsert, so now you can simply write the following
INSERT INTO...