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I right clicked a post request in Chrome and selected Copy as cURL

I got a cURL command that includes the following

 --data-binary $'------WebKitFormBound

I am used to seeing cURL requests that have a single flag and string. Like this

$curl -0 "output.txt"

I understand that the --data-binary command will post binary data (presumably after converting the string after the --databinary switch into binary). But what does the dollar sign mean?

What does the curl request mean if it has two dashes and a dollar sign?

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up vote 3 down vote accepted

The notation being used there $'...' is a special form of quoting a string recognised by a few shells like ksh (where it originated), zsh and bash.


Strings that are scanned for ANSI C like escape sequences. The Syntax is $'string'


$ echo $'hola\n'



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so basically the command says "scan the string for escape characters and print the formatted string then convert that printed string to binary" – bernie2436 Feb 17 '14 at 20:55
@akh2103 - yes I believe that's how it works. – slm Feb 17 '14 at 20:56

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