curl/docs/cmdline-opts/data.d

Long: data
Short: d
Arg: <data>
Help: HTTP POST data
Protocols: HTTP MQTT
See-also: data-binary data-urlencode data-raw
Mutexed: form head upload-file
Category: important http post upload
Example: -d "name=curl" $URL
Example: -d "name=curl" -d "tool=cmdline" $URL
Example: -d @filename $URL
---
Sends the specified data in a POST request to the HTTP server, in the same way
that a browser does when a user has filled in an HTML form and presses the
submit button. This will cause curl to pass the data to the server using the
content-type application/x-www-form-urlencoded.  Compare to --form.

--data-raw is almost the same but does not have a special interpretation of
the @ character. To post data purely binary, you should instead use the
--data-binary option.  To URL-encode the value of a form field you may use
--data-urlencode.

If any of these options is used more than once on the same command line, the
data pieces specified will be merged together with a separating
&-symbol. Thus, using '-d name=daniel -d skill=lousy' would generate a post
chunk that looks like \&'name=daniel&skill=lousy'.

If you start the data with the letter @, the rest should be a file name to
read the data from, or - if you want curl to read the data from stdin. Posting
data from a file named \&'foobar' would thus be done with --data @foobar. When
--data is told to read from a file like that, carriage returns and newlines
will be stripped out. If you don't want the @ character to have a special
interpretation use --data-raw instead.