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
specified 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 host architecture (i.e. the architecture the package
is being built for, the equivalent of DEB_HOST_ARCH).
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 approximate 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
is not set dpkg-gencontrol will compute the default value by
accumulating the size of each regular file and symlink rounded
to 1 KiB used units, and a baseline of 1 KiB for any other
filesystem object type.
Note: Take into account that this can only ever be an
approximation, as the actual size used on the installed system
will depend greatly on the filesystem used and its parameters,
which might end up using either more or less space than the
specified in this field.
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.
SEE ALSO
dpkg(1), dpkg-genchanges(1), dpkg-gencontrol(1), dpkg-shlibdeps(1), dpkg-source(1).
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