---
name: "dwarf_formref"
section: "3"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["freebsd"]
url: "https://new.carta.tech/dwarf_formref"
---

# dwarf\_formref(3)

retrieve offsets for REFERENCE class attributes

## NAME

**dwarf\_formref**, **dwarf\_global\_formref** – retrieve offsets for REFERENCE class attributes

## LIBRARY

library “libdwarf”

## SYNOPSIS

**#include \<libdwarf.h\>**

*int*\

**dwarf\_formref**(*Dwarf\_Attribute attr*, *Dwarf\_Off \*retoffset*, *Dwarf\_Error \*err*);

*int*\

**dwarf\_global\_formref**(*Dwarf\_Attribute attr*, *Dwarf\_Off \*retoffset*, *Dwarf\_Error \*err*);

## DESCRIPTION

These functions return the offsets associated with a DWARF attribute descriptor.

Function **dwarf\_formref**() returns the compilation unit relative offset of the descriptor referenced by argument *attr* in the location pointed to by argument *retoffset*. Argument *attr* must be a reference that is local to a compilation unit. Permitted forms for argument *attr* are DW\_FORM\_ref1, DW\_FORM\_ref2, DW\_FORM\_ref4, DW\_FORM\_ref8 and DW\_FORM\_ref\_udata.

Function **dwarf\_global\_formref**() returns the section-relative offset of the descriptor referenced by argument *attr* in the location pointed to by argument *retoffset*. Argument *attr* should be a legal **REFERENCE** class form. Permitted forms for argument *attr* are: DW\_FORM\_ref\_addr, DW\_FORM\_ref\_udata, DW\_FORM\_ref1, DW\_FORM\_ref2, DW\_FORM\_ref4, DW\_FORM\_ref8 and DW\_FORM\_sec\_offset. The returned offset is relative to the start of the “.debug\_info” ELF section.

If argument *err* is not NULL, it will be used to return an error descriptor in case of an error.

## RETURN VALUES

These functions return DW\_DLV\_OK on success. In case of an error, these functions return DW\_DLV\_ERROR and sets argument *err*.

## ERRORS

These functions may fail with the following errors:

- \[DW\_DLE\_ARGUMENT\]

  Either of arguments *attr* or *retoffset* was NULL.

- \[DW\_DLE\_ATTR\_FORM\_BAD\]

  The attribute referenced by argument *attr* was not of a permitted kind.

## SEE ALSO

[dwarf(3)](/dwarf/3.md), [dwarf\_attr(3)](/dwarf_attr/3.md), [dwarf\_formblock(3)](/dwarf_formblock/3.md), [dwarf\_formflag(3)](/dwarf_formflag/3.md), [dwarf\_formsdata(3)](/dwarf_formsdata/3.md), [dwarf\_formsig8(3)](/dwarf_formsig8/3.md), [dwarf\_formstring(3)](/dwarf_formstring/3.md), [dwarf\_formudata(3)](/dwarf_formudata/3.md), [dwarf\_hasattr(3)](/dwarf_hasattr/3.md)