---
name: "gendef"
section: "1"
platform: "linux"
package: "mingw-w64-tools"
version: "12.0.0-5"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/gendef"
---

# gendef(1)

DLL export extractor

## NAME

gendef - DLL export extractor

## SYNOPSIS

**gendef** \[*options*\] \<*DLL*\>

## DESCRIPTION

**gendef** dumps DLL export information from 32- and 64-bit Windows executables (respectively PE32 and PE32+ executables).

## OPTIONS

- **-**

  Dump to stdout

- **-h**, **--help**

  Briefly describe the syntax and options.

- **-a**, **--assume-stdcall**

  Assume functions with ambiguous calling conventions use stdcall.

- **-I**, **--include-def-path** \<***path***\>

  Add additional search paths in which to look for hint .def files.

- **-f**, **--no-forward-output**

  Don't output forwarders.

## OUTPUT

By default **gendef** writes the DLL export information to a file named after the DLL, replacing .dll with .def.

## KNOWN ISSUES

For 32-bit DLLs, **gendef** cannot detect if a function with no return value (void) exported by a DLL uses stdcall or cdecl. Two workarounds are available: either use the "*-a*" option to force stdcall calling conventions, or generate .def files for any DLLs the DLL you're interested in depends upon. **gendef** will read other .def files found in the working directory to determine the calling convention in use.

64-bit DLLs are not affected, since they only use a single calling convention.

## SEE ALSO

[**genidl**(1)](/genidl/1.md)

## AUTHORS

**gendef** was written by Kai Tietz and Jonathan Yong of the MinGW-w64 project.

This manual page was written by Stephen Kitt \<steve@sk2.org\>, based on information provided with the program and in the project's wiki, for the Debian GNU/Linux system (but may be used by others).