deb-substvars(5)						  dpkg utilities						  deb-substvars(5)

NAME

       deb-substvars - Debian source substitution variables

SYNOPSIS

       substvars

DESCRIPTION

       Before  dpkg-source,  dpkg-gencontrol  and dpkg-genchanges write their control information (to the source control file .dsc for dpkg-source
       and to standard output for dpkg-gencontrol and dpkg-genchanges) they perform some variable substitutions on the output file.

       A variable substitution has the form ${variable-name}.  Variable names consist of alphanumerics, hyphens  and  colons  and  start  with	an
       alphanumeric.  Variable	substitutions  are  performed repeatedly until none are left; the full text of the field after the substitution is
       rescanned to look for more substitutions.

       After all the substitutions have been done each occurrence of the string ${} (which is not a legal substitution) is replaced with a $ sign.

       While variable substitution is done on all control fields, some of those fields are used and needed during the build when the  substitution
       did not yet occur. That's why you can't use variables in the Package, Source and Architecture fields.

       Variable substitution happens on the content of the fields after they have been parsed, thus if you want a variable to expand over multiple
       lines you do not have to include a space after the newline. This is done implicitly when the field is output. For example, if the  variable
       ${Description} is set to "foo is bar.${Newline}foo is great." and if you have the following field:

	Description: foo application
	 ${Description}
	 .
	 More text.

       It will result in:

	Description: foo application
	 foo is bar.
	 foo is great.
	 .
	 More text.

       Variables  can be set using the -V common option. They can be also specified in the file debian/substvars (or whatever other file is speci-
       fied using the -T option). This file consists of lines of the form name=value.  Trailing whitespace on each line, blank	lines,	and  lines
       starting with a # symbol (comments) are ignored.

       Additionally, the following standard variables are available:

       Arch   The current build architecture (from dpkg --print-architecture).

       source:Version
	      The source package version.

       source:Upstream-Version
	      The upstream source package version, including the Debian version epoch if any.

       binary:Version
	      The binary package version (which may differ from source:Version in a binNMU for example).

       Source-Version
	      The source package version (from the changelog file). This variable is now deprecated as its meaning is different from its function,
	      please use the source:Version or binary:Version as appropriate.

       Installed-Size
	      The total size of the package's installed files. This value is copied into the corresponding control file  field;  setting  it  will
	      modify the value of that field. If this variable isn't set dpkg-gencontrol will use du -k debian/tmp to find the default value.

       Extra-Size
	      Additional  disk	space used when the package is installed. If this variable is set its value is added to that of the Installed-Size
	      variable (whether set explicitly or using the default value) before it is copied into the Installed-Size control file field.

       F:fieldname
	      The value of the output field fieldname (which must be given in the canonical capitalisation). Setting these variables has no effect
	      other than on places where they are expanded explicitly.

       Format The .changes file format version generated by this version of the source packaging scripts. If you set this variable the contents of
	      the Format field in the .changes file will change too.

       Newline, Space, Tab
	      These variables each hold the corresponding character.

       shlibs:dependencyfield
	      Variable settings with names of this form are generated by dpkg-shlibdeps.

       dpkg:Upstream-Version
	      The upstream version of dpkg.

       dpkg:Version
	      The full version of dpkg.

       If a variable is referred to but not defined it generates a warning and an empty value is assumed.

FILES

       debian/substvars
	      List of substitution variables and values.

BUGS

       The point at which field overriding occurs compared to certain standard output field settings is rather confused.

SEE ALSO

       dpkg(1), dpkg-genchanges(1), dpkg-gencontrol(1), dpkg-shlibdeps(1), dpkg-source(1).

Debian Project							    2009-07-15							  deb-substvars(5)