Puttygen on OpenVMS

PuTTygen is one of the tools used in the famous PuTTY ssh client. It's main use on OpenVMS (and elsewhere) is that it can convert private SSH keys between different formats in use.

PuTTygen on VMS docs

The partial port is based on the Unix source of PuTTy 6.2 as made available on the Putty download site. You can either download the VMS subdirectory or the full source tree including the VMS subdirectory.
Sources, including VMS Alpha executable:

The very partial VMS port, only puttygen is made working, provided by Jose Baars, and released under the same conditions as Putty itself:

To build from scratch, run command procedure @build_pg.dcl in the VMS subdirectory.

PuTTY is copyright 1997-2011 Simon Tatham.

Portions copyright Robert de Bath, Joris van Rantwijk, Delian
Delchev, Andreas Schultz, Jeroen Massar, Wez Furlong, Nicolas Barry,
Justin Bradford, Ben Harris, Malcolm Smith, Ahmad Khalifa, Markus
Kuhn, Colin Watson, and CORE SDI S.A.

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