man: Use dashes instead of underscores for variable text

This makes the text more clear by avoiding the clashes when italics
are rendered as underlined text.

debian/changelog

@@ -124,6 +124,7 @@ dpkg (1.16.1) UNRELEASED; urgency=low
       be performed interactively or from command line.
     - Add missing built-in methods to dselect(1).
     - Add missing escaping to field dashes in deb-control(5).
+    - Use dashes instead of underscores for variable text.
 
   [ Bill Allombert]
   * Add support for Build-Features: build-arch. Closes: #229357

man/deb-control.5

@@ -89,7 +89,7 @@ The name of the distribution this package is originating from.
 .TP
 .BR Bugs: " <url>"
 The url of the bug tracking system for this package. The current used format
-is \fB<bts_type>://<bts_address>\fP, like \fBdebbugs://bugs.debian.org\fP.
+is \fB<bts-type>://<bts-address>\fP, like \fBdebbugs://bugs.debian.org\fP.
 .TP
 .BR Homepage: " <url>"
 The upstream project home page URL.

man/deb-src-control.5

@@ -66,7 +66,7 @@ The upstream project home page URL.
 .TP
 .BR Bugs: " <url>"
 The url of the bug tracking system for this package. The current used format
-is \fB<bts_type>://<bts_address>\fP, like \fBdebbugs://bugs.debian.org\fP. This
+is \fB<bts-type>://<bts-address>\fP, like \fBdebbugs://bugs.debian.org\fP. This
 field is usually not needed.
 
 .TP

man/deb-version.5

@@ -2,12 +2,12 @@
 .\" The copyright given below is that of the whole policy, but probably
 .\" incomplete.
 .\" Conversion to roff by Frank Lichtenheld
-.TH deb\-version 5 "2008-08-18" "Debian Project" "Debian"
+.TH deb\-version 5 "2011-07-04" "Debian Project" "Debian"
 .SH NAME
 deb\-version \- Debian package version number format
 .
 .SH SYNOPSIS
-.RI "[ " epoch ":] " upstream_version " [\-" debian_revision " ]"
+.RI "[ " epoch ":] " upstream-version " [\-" debian-revision " ]"
 .SH DESCRIPTION
 Version numbers as used for Debian binary and source packages
 consist of three components. These are:
@@ -15,14 +15,14 @@ consist of three components. These are:
 .I epoch
 This is a single (generally small) unsigned integer.  It
 may be omitted, in which case zero is assumed.  If it is
-omitted then the \fIupstream_version\fP may not
+omitted then the \fIupstream-version\fP may not
 contain any colons.
 .IP
 It is provided to allow mistakes in the version numbers
 of older versions of a package, and also a package's
 previous version numbering schemes, to be left behind.
 .TP
-.I upstream_version
+.I upstream-version
 This is the main part of the version number.  It is
 usually the version number of the original ("upstream")
 package from which the \fI.deb\fP file has been made,
@@ -33,48 +33,48 @@ package management system's format and comparison
 scheme.
 .IP
 The comparison behavior of the package management system
-with respect to the \fIupstream_version\fP is
-described below.  The \fIupstream_version\fP
+with respect to the \fIupstream-version\fP is
+described below. The \fIupstream-version\fP
 portion of the version number is mandatory.
 .IP
-The \fIupstream_version\fP may contain only
+The \fIupstream-version\fP may contain only
 alphanumerics ("A-Za-z0-9") and the characters
 .BR . " " + " " \- " " : " " ~
 (full stop, plus, hyphen, colon, tilde) and should
 start with a digit.  If there is no
-\fIdebian_revision\fP then hyphens are not allowed;
+\fIdebian-revision\fP then hyphens are not allowed;
 if there is no \fIepoch\fP then colons are not
 allowed.
 .TP
-.I debian_revision
+.I debian-revision
 This part of the version number specifies the version of
 the Debian package based on the upstream version.  It
 may contain only alphanumerics and the characters
 .BR + " " . " " ~
 (plus, full stop, tilde) and is
 compared in the same way as the
-\fIupstream_version\fP is.
+\fIupstream-version\fP is.
 .IP
 It is optional; if it isn't present then the
-\fIupstream_version\fP may not contain a hyphen.
+\fIupstream-version\fP may not contain a hyphen.
 This format represents the case where a piece of
 software was written specifically to be turned into a
 Debian package, and so there is only one "debianisation"
 of it and therefore no revision indication is required.
 .IP
 It is conventional to restart the
-\fIdebian_revision\fP at '1' each time time the
-\fIupstream_version\fP is increased.
+\fIdebian-revision\fP at '1' each time time the
+\fIupstream-version\fP is increased.
 .IP
 Dpkg will break the version
 number apart at the last hyphen in the string (if there
-is one) to determine the \fIupstream_version\fP and
-\fIdebian_revision\fP.  The absence of a
-\fIdebian_revision\fP compares earlier than the
-presence of one (but note that the \fIdebian_revision\fP
+is one) to determine the \fIupstream-version\fP and
+\fIdebian-revision\fP. The absence of a
+\fIdebian-revision\fP compares earlier than the
+presence of one (but note that the \fIdebian-revision\fP
 is the least significant part of the version number).
 .SS Sorting Algorithm
-The \fIupstream_version\fP and \fIdebian_revision\fP
+The \fIupstream-version\fP and \fIdebian-revision\fP
 parts are compared by the package management system using the
 same algorithm:
 .PP

man/dpkg-deb.1

@@ -186,11 +186,11 @@ explanation of the \fB\-\-showformat\fP option in
 
 The default for this field is "${Package}\\t${Version}\\n".
 .TP
-.BI \-z compress_level
+.BI \-z compress-level
 Specify which compression level to pass to the compressor backend program,
 when building a package.
 .TP
-.BI \-Z compress_type
+.BI \-Z compress-type
 Specify which compression type to use when building a package. Allowed
 values are \fIgzip\fP, \fIxz\fP, \fIbzip2\fP, \fIlzma\fP, and \fInone\fP
 (default is \fIgzip\fP).

man/dpkg-gensymbols.1

@@ -317,9 +317,9 @@ using an include directive like this:
 .IP \(bu
 The include directive may also be tagged like any symbol:
 
-(tag|..|tagN)#include "file_to_include"
+(tag|..|tagN)#include "file-to-include"
 
-As a result, all symbols included from \fIfile_to_include\fR will be considered
+As a result, all symbols included from \fIfile-to-include\fR will be considered
 to be tagged with \fItag\fR .. \fItagN\fR by default. You can use this feature
 to create a common \fIpackage\fR.symbols file which includes architecture
 specific symbol files:

man/dpkg-name.1

@@ -20,10 +20,10 @@ This manual page documents the
 program which provides an easy way to rename
 .B Debian
 packages into their full package names. A full package name consists
-of \fI<package>_<version>_<architecture>.<package_type>\fP as specified in
+of \fI<package>_<version>_<architecture>.<package-type>\fP as specified in
 the control file of the package. The \fI<version>\fP part of the filename
 consists of the upstream version information optionally followed by a
-hyphen and the revision information. The \fI<package_type>\fP part comes
+hyphen and the revision information. The \fI<package-type>\fP part comes
 from that field if present or fallbacks to \fBdeb\fP.
 .
 .SH OPTIONS

man/dpkg.1

@@ -88,9 +88,9 @@ option \fB\-\-force\-remove\-reinstreq\fP.
 .
 .SH ACTIONS
 .TP
-\fB\-i\fP, \fB\-\-install\fP \fIpackage_file\fP...
+\fB\-i\fP, \fB\-\-install\fP \fIpackage-file\fP...
 Install the package. If \fB\-\-recursive\fP or \fB\-R\fP option is
-specified, \fIpackage_file\fP must refer to a directory instead.
+specified, \fIpackage-file\fP must refer to a directory instead.
 
 Installation consists of the following steps:
 .br
@@ -119,9 +119,9 @@ time old files are removed.
 \fB6.\fP Configure the package. See \fB\-\-configure\fP for detailed
 information about how this is done.
 .TP
-\fB\-\-unpack \fP\fIpackage_file\fP...
+\fB\-\-unpack \fP\fIpackage-file\fP...
 Unpack the package, but don't configure it. If \fB\-\-recursive\fP or
-\fB\-R\fP option is specified, \fIpackage_file\fP must refer to a
+\fB\-R\fP option is specified, \fIpackage-file\fP must refer to a
 directory instead.
 .TP
 \fB\-\-configure \fP\fIpackage\fP...|\fB\-a\fP|\fB\-\-pending\fP
@@ -193,10 +193,10 @@ file is \fBdselect update\fR. Note that this file is mostly useless
 if you don't use \fBdselect\fR but an APT-based frontend: APT has its
 own system to keep track of available packages.
 .TP
-\fB\-A\fP, \fB\-\-record\-avail\fP \fIpackage_file\fP...
+\fB\-A\fP, \fB\-\-record\-avail\fP \fIpackage-file\fP...
 Update \fBdpkg\fP and \fBdselect\fP's idea of which packages are
-available with information from the package \fIpackage_file\fP. If
-\fB\-\-recursive\fP or \fB\-R\fP option is specified, \fIpackage_file\fP
+available with information from the package \fIpackage-file\fP. If
+\fB\-\-recursive\fP or \fB\-R\fP option is specified, \fIpackage-file\fP
 must refer to a directory instead.
 .TP
 .B \-\-forget\-old\-unavail