---
name: "deb-symbols"
section: "5"
platform: "linux"
package: "dpkg"
version: "1.23.11-1"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/deb-symbols"
---

# deb-symbols(5)

Debian's extended shared library information file

## NAME

deb-symbols - Debian's extended shared library information file

## SYNOPSIS

**DEBIAN/symbols**

## DESCRIPTION

The symbol files are shipped in Debian binary packages, and its format is a subset of the template symbol files used by [**dpkg-gensymbols**(1)](/dpkg-gensymbols/1.md) in Debian source packages, see [**deb-src-symbols**(5)](/deb-src-symbols/5.md).

A **symbols** file must be shipped in the same binary package as the shared libraries described within. This is to guarantee that the symbols descriptions match the shared library being described, and so that the **symbols** file can be found from the package owning the shared library.

The format for an extended shared library dependency information entry in these files is:

 *library-soname* *main-dependency-template*\
  \[\| *alternative-dependency-template*\]\
  \[...\]\
  \[\* *field-name*: *field-value*\]\
  \[...\]\
   *symbol* *minimal-version* \[*id-of-dependency-template*\]

The *library-soname* is exactly the value of the SONAME field as exported by [**objdump**(1)](/objdump/1.md). A *dependency-template* is a dependency where *#MINVER#* is dynamically replaced either by a version check like “(\>= *minimal-version*)” or by nothing (if an unversioned dependency is deemed sufficient).

Each exported *symbol* (listed as *name*@*version*, with *version* being “Base” if the library is not versioned) is associated to a *minimal-version* of its dependency template (the main dependency template is always used and will end up being combined with the dependency template referenced by *id-of-dependency-template* if present). The first alternative dependency template is numbered 1, the second one 2, etc. Each column is separated by exactly a single whitespace.

Each entry for a library can also have some fields of meta-information. Those fields are stored on lines starting with an asterisk. Currently, the only valid fields are:

- **Build-Depends-Package**

  It indicates the name of the “-dev” package associated to the library and is used by **dpkg-shlibdeps** to make sure that the dependency generated is at least as strict as the corresponding build dependency.

  Supported since dpkg 1.14.13.

- **Build-Depends-Packages**

  The same as **Build-Depends-Package** but accepts a comma-separated list of package names. This field will override any **Build-Depends-Package** field present, and is mostly useful with “-dev” packages and metapackages depending on these, say for a transition period.

  Supported since dpkg 1.20.0.

- **Allow-Internal-Symbol-Groups**

  It indicates what internal symbol groups should be ignored, as a whitespace separated list, so that the symbols contained in those groups get included in the output file. This should only be necessary for toolchain packages providing those internal symbols. The available groups are system dependent, for ELF and GNU-based systems these are **aeabi** and **gomp**.

  Supported since dpkg 1.20.1.

## EXAMPLES

### Simple symbols file

```
 libftp.so.3 libftp3 #MINVER#
  DefaultNetbuf@Base 3.1-1-6
  FtpAccess@Base 3.1-1-6
  [...]
```

### Advanced symbols file

```
 libGL.so.1 libgl1
 | libgl1-mesa-glx #MINVER#
 * Build-Depends-Package: libgl1-mesa-dev
  publicGlSymbol@Base 6.3-1
  [...]
  implementationSpecificSymbol@Base 6.5.2-7 1
  [...]
```

## SEE ALSO

\<https://wiki.debian.org/Projects/ImprovedDpkgShlibdeps\>, [**deb-src-symbols**(5)](/deb-src-symbols/5.md), [**dpkg-shlibdeps**(1)](/dpkg-shlibdeps/1.md), [**dpkg-gensymbols**(1)](/dpkg-gensymbols/1.md).