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How can I get a file's size in C? [duplicate]
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You need to seek to the end of the file and then ask for the position:
fseek(fp, 0L, SEEK_END);
sz = ftell(fp);
You can then seek back, e.g.:
fseek(fp, 0L, SEEK_SET);
or (if seeking to go to the beginning)
rewind(fp);
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Printing newlines with print() in R
.../program F=filename")
File not supplied.
Usage: ./program F=filename>
and
> cat("File not supplied.\nUsage: ./program F=filename","\n")
File not supplied.
Usage: ./program F=filename
>
The reason print() doesn't do what you want is that print() shows you a version of the object from th...
Replace a value in a data frame based on a conditional (`if`) statement
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Easier to convert nm to characters and then make the change:
junk$nm <- as.character(junk$nm)
junk$nm[junk$nm == "B"] <- "b"
EDIT: And if indeed you need to maintain nm as factors, add this in the end:
junk$nm <- as.factor(junk$nm)
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uppercase first character in a variable with bash
...t Bash), the overhead of using a here-doc/string (temporary file creation) and it uses two substitutions compared to the best scored answer's one. If you absolutely must write legacy code, consider using a function instead of a subshell.
– Steve
Apr 13 '16 at 2...
Detect Safari using jQuery
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Using a mix of feature detection and Useragent string:
var is_opera = !!window.opera || navigator.userAgent.indexOf(' OPR/') >= 0;
var is_Edge = navigator.userAgent.indexOf("Edge") > -1;
var is_chrome = !!window.chrome && !is_opera...
psql: FATAL: role “postgres” does not exist
...ep is to check the missing role: What is the output within psql of the command \du ? On my Ubuntu system the relevant line looks like this:
List of roles
Role name | Attributes | Member of
-----------+-----------------------------------+-------...
How to access the GET parameters after “?” in Express?
...e value I'm looking for.
req.params refers to items with a ':' in the URL and req.query refers to items associated with the '?'
Example:
GET /something?color1=red&color2=blue
Then in express, the handler:
app.get('/something', (req, res) => {
req.query.color1 === 'red' // true
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How do you make lettered lists using markdown?
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It doesn't appear that standard Markdown has this capability. You can:
Use CSS, by putting this somewhere in your markdown document (note, this will effect all ordered lists in the document)
<style type="text/css">
ol { list-style-type: u...
Any way to write a Windows .bat file to kill processes? [closed]
...rocesses from programs that my company installs on my machine for security and compliance. What I'd like to do is have a .bat file or script of some kind with which I can kill the processes in question.
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Run cURL commands from Windows console
Is there a way to install cURL in Windows in order to run cURL commands from the command prompt?
21 Answers
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