curl: read headers from file

Question

After the --dump-header writes a file, how to read those headers back into the next request? I would like to read them from a file because there are a number of them.

I tried standard in: cat headers | curl -v -H - ...

I'm actually using the feature in Firebug to "Copy Request Headers" and then saving those to a file. This appears to be the same format.

Answer 1

since curl 7.55.0

Easy:

$ curl -H @header_file $URL 

... where the header file is a plain text file with a HTTP header on each line. Like this:

Color: red Shoesize: 11 Secret: yes User-Agent: foobar/3000 Name: "Joe Smith" 

before curl 7.55.0

curl had no way to "bulk change" headers like that, not even from a file.

Your best approach with an old curl version is probably to instead write a shell script that gathers all the headers from the file and use them, like:

#!/bin/sh while read line; do   args="$args -H '$line'"; done curl $args $URL 

Invoke the script like this:

$ sh script.sh < header_file 

Answer 2

how about this:

curl -v -H "$(cat headers.txt)" yourhost.com 

where headers.txt looks like

Header1: bla Header2: blupp 

works in BASH.