.\" dpkg manual page - dpkg-trigger(1)
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.\" Copyright © 2008-2015 Guillem Jover <guillem@debian.org>
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.TH dpkg\-trigger 1 "2018-06-26" "1.18.25" "dpkg suite"
.nh
.SH NAME
dpkg\-trigger \- a package trigger utility
.
.SH SYNOPSIS
.B dpkg\-trigger
.RI [ option "...] " trigger-name
.br
.B dpkg\-trigger
.RI [ option "...] " command
.
.SH DESCRIPTION
\fBdpkg\-trigger\fP is a tool to explicitly activate triggers and check
for its support on the running \fBdpkg\fP.
.PP
This can be used by maintainer scripts in complex and conditional
situations where the file triggers, or the declarative \fBactivate\fP
triggers control file directive, are insufficiently rich. It can also
be used for testing and by system administrators (but note that the
triggers won't actually be run by \fBdpkg\-trigger\fP).
.PP
Unrecognized trigger name syntaxes are an error for \fBdpkg\-trigger\fP.
.
.SH COMMANDS
.TP
.BR \-\-check\-supported
Check if the running \fBdpkg\fP supports triggers (usually called from a
postinst). Will exit \fB0\fP if a triggers-capable \fBdpkg\fP has run,
or \fB1\fP with an error message to stderr if not. Normally, however,
it is better just to activate the desired trigger with \fBdpkg\-trigger\fP.
.TP
.BR \-? ", " \-\-help
Show the usage message and exit.
.TP
.B \-\-version
Show the version and exit.
.
.SH OPTIONS
.TP
.BI \-\-admindir= dir
Change the location of the \fBdpkg\fR database. The default location is
\fI/var/lib/dpkg\fP.
.TP
.BR \-\-by\-package=\fIpackage\fR
Override trigger awaiter (normally set by \fBdpkg\fP through the
\fBDPKG_MAINTSCRIPT_PACKAGE\fP environment variable of the maintainer scripts,
naming the package to which the script belongs, and this will be used
by default).
.TP
.BR \-\-no\-await
This option arranges that the calling package T (if any) need not await
the processing of this trigger; the interested package(s) I, will not be
added to T's trigger processing awaited list and T's status is unchanged.
T may be considered installed even though I may not yet have processed
the trigger.
.TP
.BR \-\-await
This option does the inverse of \fB\-\-no\-await\fP (since dpkg 1.17.21).
It is currently the default behavior.
.TP
.BR \-\-no\-act
Just test, do not actually change anything.
.
.SH EXIT STATUS
.TP
.B 0
The requested action was successfully performed.
Or a check or assertion command returned true.
.TP
.B 1
A check or assertion command returned false.
.TP
.B 2
Fatal or unrecoverable error due to invalid command-line usage, or
interactions with the system, such as accesses to the database,
memory allocations, etc.
.
.SH ENVIRONMENT
.TP
.B DPKG_ADMINDIR
If set and the \fB\-\-admindir\fP option has not been specified, it will
be used as the \fBdpkg\fP data directory.
.
.SH SEE ALSO
.BR dpkg (1),
.BR deb\-triggers (5),
.\" FIXME: Unhardcode the pathname, and use dpkg instead of dpkg-dev.
.BR /usr/share/doc/dpkg\-dev/triggers.txt.gz .