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-gencon‐
       trol and dpkg-genchanges) they perform some variable substitutions on the output file.

       A variable substitution has the form ${variable-name}.  Variable names consist of alphanu‐
       merics, hyphens and colons and start with an alphanumeric. Variable substitutions are per‐
       formed  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 specified using the -T option). This file con‐
       sists 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 depre‐
              cated 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 cor‐
              responding 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 capi‐
              talisation). 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.

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



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