confmodule - communicate with Debian configuration system FrontEnd.
     #!/bin/sh -e
     . /usr/share/debconf/confmodule
     db_version 2.0
     db_capb 'backup'
     CAPB=$RET
     db_input 'foo/bar' || true
     db_go || true
This is a library of shell functions that eases communication with Debian's configuration management system. It can communicate with a FrontEnd via the debconf protocol. The design is that each command in the protocol is represented by one function in this module. The functionname is the same as the command, except it is prefixed with "db_" and is lower-case. Call the function and pass in any parameters you want to follow the command. Any textual return code from the FrontEnd will be returned to you in the $RET variable, while the numeric return code from the FrontEnd will be returned as a return code (and so those return codes must be captured or ignored).
   Once this library is loaded, any text  you  later  output  will  go  to
   standard  error,  rather  than standard output. This is a good thing in
   general, because text sent to standard output  is  interpreted  by  the
   FrontEnd  as commands. If you do want to send a command directly to the
   FrontEnd, you must output it to file descriptor 3, like this:
     echo GET foo/bar >&3
   The library checks to make sure it is actually speaking to  a  FrontEnd
   by examining the DEBIAN_HAS_FRONTEND variable. If it is set, a FrontEnd
   is assumed to be running. If not, the library turns into one, and  runs
   a  copy  of  the  script  that loaded the library connected to it. This
   means that if you source this library, you should do so  very  near  to
   the  top  of your script, because everything before the sourcing of the
   library may well be run again.
debconf-devel(7), dpkg-preconfigure(8), dpkg-reconfigure(8), debconf_specification in the debian-policy package
Joey Hess <[email protected]> CONFMODULE(3)
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