NAME

       deb-triggers - package triggers

SYNOPSIS

       triggers

DESCRIPTION

       A package declares its relationship to some trigger(s) by including a triggers file in its
       control archive (i.e. DEBIAN/triggers during package creation).

       This file  contains  directives,  one  per  line.  Leading  and  trailing  whitespace  and
       everything after the first # on any line will be trimmed, and empty lines will be ignored.

       The trigger control directives currently supported are:

       interest trigger-name
       interest-await trigger-name
       interest-noawait trigger-name

              Specifies  that  the  package  is  interested in the named trigger. All triggers in
              which a package is interested must be listed using this directive in  the  triggers
              control file.

              The “await” variants put the triggering package in triggers-awaited state depending
              on how the  trigger  was  activated.   The  “noawait”  variant  does  not  put  the
              triggering  packages  in  triggers-awaited  state,  even  if the triggering package
              declared  an  “await”  activation  (either  with  an  activate-await  or   activate
              directive,  or  by  using  the  dpkg-trigger  --no-await command-line option).  The
              “noawait” variant should be used when the functionality provided by the trigger  is
              not crucial.

       activate trigger-name
       activate-await trigger-name
       activate-noawait trigger-name

              Arranges  that changes to this package's state will activate the specified trigger.
              The trigger will be activated at the start of  the  following  operations:  unpack,
              configure,  remove  (including for the benefit of a conflicting package), purge and
              deconfigure.

              The “await” variants only put the triggering package in triggers-awaited  state  if
              the  interest  directive  is  also  “await”.   The “noawait” variant never puts the
              triggering packages in triggers-awaited state.  The  “noawait”  variant  should  be
              used when the functionality provided by the trigger is not crucial.

              If this package disappears during the unpacking of another package the trigger will
              be activated when the disappearance is noted towards the end of the unpack. Trigger
              processing,  and  transition  from  triggers-awaited  to  installed, does not cause
              activations.  In the case of unpack, triggers mentioned in both  the  old  and  new
              versions of the package will be activated.

       Unknown directives are an error which will prevent installation of the package.

       The  “-noawait”  variants should always be favored when possible since triggering packages
       are not put in triggers-awaited state and  can  thus  be  immediately  configured  without
       requiring  the  processing of the trigger.  If the triggering packages are dependencies of
       other upgraded packages, it will avoid  an  early  trigger  processing  run  and  make  it
       possible to run the trigger only once as one of the last steps of the upgrade.

       The  “-noawait”  variants are supported since dpkg 1.16.1, and will lead to errors if used
       with an older dpkg.

       The “-await” alias variants are supported since dpkg 1.17.21, and will lead to  errors  if
       used with an older dpkg.

       When  a  package  provides  an  interest-noawait  directive,  any  activation will set the
       triggering package into “noawait” mode, regardless of the awaiting mode requested  by  the
       activation  (either  “await”  or  “noawait”).   When  a  package  provides  an interest or
       interest-await directive, any activation will set the triggering package into  “await”  or
       “noawait“ depending on how it was activated.

SEE ALSO

       dpkg-trigger(1), dpkg(1), /usr/share/doc/dpkg-dev/triggers.txt.gz.