variable.md 1.9 KB
c: Copyright (C) Daniel Stenberg, daniel@haxx.se, et al. SPDX-License-Identifier: curl Long: variable Arg: <[%]name=text/@file> Help: Set variable Category: curl Added: 8.3.0 Multi: append See-also:
- config Example:
- --variable name=smith $URL ---
--variable
Set a variable with name=content or name@file (where file can be stdin
if set to a single dash (-)). The name is a case sensitive identifier that
must consist of no other letters than a-z, A-Z, 0-9 or underscore. The
specified content is then associated with this identifier.
Setting the same variable name again overwrites the old contents with the new.
The contents of a variable can be referenced in a later command line option
when that option name is prefixed with --expand-, and the name is used as
{{name}}.
--variable can import environment variables into the name space. Opt to either require the environment variable to be set or provide a default value for the variable in case it is not already set.
--variable %name imports the variable called name but exits with an error if
that environment variable is not already set. To provide a default value if
the environment variable is not set, use --variable %name=content or
--variable %name@content. Note that on some systems - but not all -
environment variables are case insensitive.
When expanding variables, curl supports a set of functions that can make the variable contents more convenient to use. You apply a function to a variable expansion by adding a colon and then list the desired functions in a comma-separated list that is evaluated in a left-to-right order. Variable content holding null bytes that are not encoded when expanded, causes an error.
Available functions:
trim
removes all leading and trailing white space.
json
outputs the content using JSON string quoting rules.
url
shows the content URL (percent) encoded.
b64
expands the variable base64 encoded