---
name: "canlock-hfp"
section: "1"
platform: "linux"
package: "canlock"
version: "3.3.1-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/canlock-hfp"
---

# canlock-hfp(1)

CLI frontend for libcanlock library

## NAME

canlock-hfp - CLI frontend for libcanlock library

## SYNOPSIS

**canlock-hfp** -h \| -v

**canlock-hfp** \[-d\] \[-n\]

## DESCRIPTION

Header Field Parser (hfp) for RFC 8315 conformant header fields.

The header field is read from stdin.

The input data must be an unfolded "Cancel-Lock" or "Cancel-Key" header field without line break at the end. The utility [**canlock-mhp**(1)](/canlock-mhp/1.md) can be used to extract the field from an article.

If such a header field is found, it is parsed according to the syntax defined in RFC 8315. If valid c-lock or c-key (respectively) elements are found, they are printed to stdout with SP (Space) as delimiter.

Note: Additional formatting output is printed on stderr to make the output more human readable on a terminal. Redirect stderr to /dev/null if this is not wanted.

## OPTIONS

The following options are supported:

- **-d**

  Enable debug mode (messages are printed to stderr).

- **-h**

  Print help message, then exit.

- **-n**

  Prepend the data on stdout with the header field name (including the colon) and a SP (Space) delimiter.

- **-v**

  Print version and compile time options, then exit.

## EXIT STATUS

Zero on success or regular exit respectively.\
 All other values indicate an error.

## AUTHORS

Michael Baeuerle

## REPORTING BUGS

Report bugs to \<mailto:michael.baeuerle@gmx.net\>.

## STANDARDS

**canlock-hfp** tries to comply with the following standards:

RFC 8315

## SEE ALSO

[**canlock-mhp**(1)](/canlock-mhp/1.md), [**canlock**(1)](/canlock/1.md)